When Patrick Pacious, the chief executive of a large portfolio of hotel brands, promoted a blockbuster attempt to acquire a competitor in October, he said the proposed merger would lower costs and attract more customers for the families and small businesses that own most of the company’s locations.

“Our franchisees instantly grasped the strategic benefit this would bring to their hotels,” Mr. Pacious, who leads Choice Hotels, said on CNBC.

As the weeks have passed, however, the reaction has not been positive. Wyndham Hotels and Resorts, the target of the proposed deal, rejected the offer from Choice, which is now pursuing a hostile takeover. And in early December, an association representing the majority of hoteliers who own Choice and Wyndham-branded properties came out strongly against it.

“We all don’t know what’s driving this merger. Many of us feel it’s not needed,” said Bharat Patel, the chairman of the organization, the Asian American Hotel Owners Association. The group surveyed its 20,000 members and found that about 77 percent of respondents who own hotels under either brand or both thought a merger would hurt their business.

“I’m not against Choice or Wyndham,” said Mr. Patel, who owns two Choice hotels. “We just need robust competition in the markets.”

That opposition illustrates a growing resistance to consolidation in industries that have grown more concentrated in recent years. Even some Wall Street analysts have expressed skepticism that Choice’s proposal is a good idea.

The views of hotel owners could become a hurdle for Choice as it seeks approval for a merger from the Federal Trade Commission, which has taken an interest in franchising as evidence has mounted that the economic and legal relationship has increasingly tilted in favor of brand owners and away from franchisees.

To understand why franchisees are worried, it’s helpful to understand how hotels are structured.

About 70 percent of the nation’s 5.7 million hotel rooms operate under one of the several big national brands like Marriott or Hilton, according to the real estate data firm CoStar. The rest are independent.

Over the past few decades, franchise chains have bought one another and merged to the point where the top six companies by number of rooms — Marriott, Hilton, InterContinental, Best Western, Choice and Wyndham — account for about 80 percent of all branded hotels.

Unlike fast food franchisees, hotel owners typically develop or buy their own buildings, representing a multimillion-dollar investment for each property. The industry has drawn thousands of immigrant entrepreneurs from South Asia. Some owners accumulate sprawling portfolios, but most end up with just a few hotels.

The average member of the Asian American owners’ group owns just two hotels, most commonly with one of the economy or midscale brands. Choice and Wyndham dominate that segment, with 6,270 and 5,907 hotels in the United States, including Days Inn, Howard Johnson, Quality Inn and Econo Lodge.

Being part of a franchise network provides a recognized name, a business plan and collective purchasing that is supposed to give small businesses the benefits of scale. In exchange, hotel owners pay the brands a fee to join, ongoing royalties and other payments for marketing, technology and consulting.

As a result, franchisees are effectively customers of the hotel brands. Less competition between hotel chains can leave owners with fewer options and, thus, less leverage to demand better services for a lower cost.

Consider the frustrations of Jayanti Patel, who owns a Comfort Inn — one of Choice’s 22 brands — in Gettysburg, Pa.

He said Choice had been taking a larger cut, via charges like an $18 monthly fee for reporting his property’s energy use, discounts for rooms booked with rewards programs and penalties when guests file complaints. Mr. Patel also laments declining service, such as from revenue management consultants who are supposed to provide advice that increases his profits. Choice has outsourced this work to a service that operates partly overseas.

Mr. Patel said his profit margins had become “thinner and thinner,” and he’s considering signing up with a different brand when his franchise agreement ends in a couple of years. Friends who own Wyndham-branded properties seem happy, so he might adopt one of its brands as long as Choice doesn’t acquire that chain.

“When my window comes up in 2026, 99 percent I don’t want to renew my agreement,” Mr. Patel said. “And maybe If I want to go to Wyndham, they have nearly 20 brands, and I lose that opportunity, because it will be the same thing.”

Choice argues that as its rivals have expanded and merged, it also needs to grow to offer hotel owners bigger savings on supplies like signage and bedsheets. The company is also promising to bargain down the commissions that hotel owners pay websites like Expedia and Booking.com, which are particularly crucial in the budget segment.

“Combining with Wyndham would enable us to continue to deliver enhanced profitability for franchisees — by helping to lower their costs and grow their direct revenue while providing our best-in-class technology platform,” Choice said in a statement.

However, many hotel owners say that even if Choice did negotiate lower prices, they are skeptical that they would reap those benefits. In 2020, 90 franchisees filed a lawsuit that accused the company of, among other things, not passing along rebates from contracts with vendors. A judge ruled that hotel owners would have to pursue their claims in separate arbitration cases, and several did.

Choice prevailed in two of those proceedings. But in one, brought by a hotelier in North Dakota, an arbitrator found this past summer that Choice had “made virtually no efforts to leverage its size, scale and distribution to obtain volume discounts.” He ordered Choice to pay $760,008 in legal fees and compensation. Choice is contesting the award.

The case is just one example, but it squares with recent economic research. A 2017 study found that while being part of a hotel franchise system helped bring in guests, it did not lower the cost of doing business compared with operating an independent hotel.

But litigating on your own is expensive, which is why few franchisees do so even when they feel they’ve been mistreated.

Rich Gandhi, a hotelier in New Jersey, is supporting a campaign for state legislation that would improve the rights of franchisees in the hospitality industry. He leads a three-year-old group called Reform Lodging that is also opposing the merger.

Mr. Gandhi has turned four of his Choice-branded hotels into Best Westerns and Red Roof Inns, both non-Choice brands that he said offered better assistance, fewer restrictions and more reasonable fees. Choice, he argued, introduced too many competitors to his area because it makes money from selling new franchises and controlling more of the market, even if the practice squeezes existing owners.

“They want the biggest pie, because to them it’s all incremental revenue,” Mr. Gandhi said. “If you keep accumulating all these buildings and provide no support, it’s like one of those old pyramid schemes that’s ready to fall apart, which is exactly what’s happening.”

A representative for Choice referred The New York Times to four hoteliers who it said would speak favorably of the merger. Two of them, including the chairman of the Choice Hotels Owners Council — to which all franchisees must belong and pay dues — declined to comment on the record. A third, who owns three Radisson hotels and was happy when Choice bought the brand, said the purchase of Wyndham — a much bigger company — could pose problems.

The fourth, a Florida hotelier, Azim Saju, said that despite the loss of competition, if Choice acquired Wyndham the company would still have an incentive to make sure franchisees stayed afloat.

“The concern is valid, but the bottom line is that franchising doesn’t do well unless the franchisees are profitable,” Mr. Saju said. “I think Choice has become more conscientious of the importance of franchisee profitability in order to further their success.”

The dissatisfaction of hotel owners could hurt Choice’s ability to absorb Wyndham, especially if more franchisees switch to other brands. That prospect has soured some Wall Street analysts on the deal.

“In hotel franchising, the critical constituency, as much as consumers walking in the door, is that franchising community,” said David Katz, an analyst who covers the hospitality and gambling industries for Jefferies & Company. “They’re going to own more than 50 percent of the limited service and economy hotels in the United States, and not have the full support of the largest franchisee organization out there? I think that merits further debate.”

Franchisee support isn’t important just for morale. It could also sway federal regulators, who have started to take into account the effect of corporate mergers not just on their consumers but also on suppliers like book authors, chicken farmers and Amazon sellers.

“Traditionally in antitrust there’s this consumer welfare standard, which is focused on ‘Is this going to be good or bad for consumers?’” said Brett Hollenbeck, an associate professor at the Anderson School of Management of the University of California, Los Angeles. “If the F.T.C. doesn’t feel like this argument will hold sway, they could try a more novel theory, which is that it could hurt franchisees.”

Choice said it anticipated that its deal would be approved and was expecting to complete the transaction within a year. Its offer to buy all outstanding Wyndham shares extends through March, when it will try to replace the directors on the company’s board with people who will approve the sale.