When the popular Numbers dance club at 1330 19th St. NW posted a notice to its "regular" customers that Sunday would henceforth be reserved for gay "tea dances" the move was met with scorn by some in the City's gay community.

"It happens all the time," scoffed one restaurateur. "Whenever a bar is about to go out of business, they turn around and go gay."

The sign on the door at Numbers and its nongay ownership drew accusations of exploitation from some gay activists, among them the Rev. Larry J. Uhrig, pastor of the gay Metropolitan Community Church, 945 G St. NW. Uhrig and other critics dashed off heated letters to the city's gay weekly newspaper, The Washington Blade.

But the criticism notwithstanding, hundreds of gay men and women continue to gather at the Dupont Circle bar on Sunday evenings. The bar's owner, who asked not to be named, said business has never been better.

Inspired by surveys linking gays to high incomes and lavish spending, businesses throughout the District and nationwide are courting gay customers. The entry of straight-owned businesses into that lucrative market has sparked disagreement among some gay customers over whether to be loyal to gay-owned businesses or to frequent the straight-owned establishments.

"I was concerned mainly because of the sign, which implied we were 'irregular' customers and only welcome in the bar on Sundays," said Uhrig, who still boycotts Numbers.

"A lot of businesses have been trying to get gay people to patronize them lately, particularly in Dupont Circle and Adams-Morgan. But we have to ask ourselves, are they really serious about supporting the gay community or are they just trying to get our money?"

Bars that attract gays are traditionally gay owned. Yet the owners of many straight bars think gays, particularly men, earn more, spend more and tip better than straight customers.

Kramerbooks & Afterwords Cafe, a bookstore and restaurant at 1517 Connecticut Ave. NW, has advertised in gay publications and has stocked gay books for years, coowner David Tenney said.

"It's just good business," Tenney said. "We feel the more different kinds of people we cater to, the richer we will be for it."

Acapulco, a small Mexican restaurant at 2450 18th St. NW, last month hired two female impersonators for a weekend "drag show" that owner Manolo Solloso said he hopes will attract Adams-Morgan gays, many of whom frequent nearby Morgan's, 1811 Columbia Rd. NW.

"I've tried disco, I've tried Latin music, and people don't enter my restaurant," said Spanish-born Solloso. "This time, I think they will enter."

Robert Novelle, coowner of Morgan's, is skeptical about the drag show's success, calling it "a gimmick."

"The reason Morgan's is so successful is because we opened as a gay bar," he said. "My partners are gay, my staff is gay. . . . We're not just out to make a fast buck. When you're dealing with a minority group, you have a certain responsibility to them."

Jeff Levi, president of the local Gay Activist Alliance, said he views straight advertisers as inevitable competition in a free-market economy.

"There's a common stereotype that because we are men and because we are single we have more money to spend," Levi said. "I should be so lucky to have some of that money."

The stereotypes are supported by statistics compiled by the California-based national gay magazine, The Advocate, and its market research firm, Avanti.

When the Advocate surveyed its 73,000 subscribers in 1977, it found gays had an average yearly income of $23,600 per household of 1.4 members, 50 percent higher than the national average. Findings in Avanti's 1982 random survey of 1,300 gay men in 11 U.S. cities, including Washington, set the figure at $31,300.

The Advocate now attracts advertising from Seagram's and other liquor companies, most movie studios and financial institutions, such as Dean Witter Reynolds Inc. and the Oppenheimer Fund.

This trend has been followed locally, with such large companies as Kemp Mill Records and Koons Ford now advertising in The Washington Blade.

"Our ad sales from straight businesses are way up," Blade editor Steve Martz said. "People are finally realizing there's money in the gay community, and they're going after it."

Kemp Mill Records vice president Howard Appelbaum said he started advertising in the Blade five months ago because "it's a good life-style paper with an exclusive readership--and frankly, because none of the other papers were doing it."

Mimi Weidlein, Koons Ford's assistant marketing director, said her company's three-month Blade ad was "an experiment in a new market" that has been "quite successful."

Shannon Rodes, advertising director of the Blade, said this ad business is not exploitation but is a way of dispelling some myths about gay life.

"People never used to think of gays as homeowners," Rodes said. "Then real estate agencies started advertising with us and were very successful. They found that gays had more money, had an easier time getting credit, were willing to buy in 'fringe' areas and actually turned many of those neighborhoods around."

One real estate agent, Grant Griffith of Dale Denton Real Estate, said he was "taking a risk" when he bought a one-month Blade ad but promptly sold his M Street house to a Blade reader and plans to use the paper again.

Avanti pollster Jim Mayer said many gay consumers "actually look through a publication like the Advocate and purchase from a business that advertises there because they see it as a political statement."

But such tactics can backfire, Uhrig said, if businesses do not also show an interest in gay issues.

"There are a lot of questions you have to ask when a business suddenly starts trying to attract gay customers. Are they willing to endorse gay politicians? Will they hire gay employes?"

Numbers, surprised at such scrutiny, removed its controversial sign and now sponsors benefits for gay institutions, such as the Whitman Walker gay health clinic, 2335 l8th St. NW.

One stereotype that lingers despite the increase of straight advertising in gay media is that lesbians, unlike gay men, are not big spenders.

"People still tend to think of us as walking around in plaid work shirts, as people not really committed to spending money," Rodes said.

Several business owners who cater specifically to gay men say lesbians are simply "less visible," and as women they naturally earn less than men.

The Avanti surveys, for example, excluded lesbians. Mayer contended "there is just not as great an interest in the lesbian market." The Advocate's readership is 95 percent male, he said.

Similarly, the majority of the Blade's readers are male, according to administrative coordinator Ann Bemis. "This is largely for economic reasons," she said. "It just so happens that gay women are much more closeted than men."