MOUND HOUSE, Nevada – In a small Nevada town, a sign at the end of a poorly lighted street lined with warehouses bears an unusual message: “Warning-Sexual entertainment 300 yards ahead. If sex offends you, get out of here.”

At the Bunny Ranch in Mound House, men travel many miles to spend hundreds or even thousands of dollars to have sex in the only U.S. state to allow legal brothels.

Yet even in permissive Nevada, legal prostitution operates at the margins of society and, unlike other vices such as gambling and pornography, without mainstream America’s embrace. The brothel owners themselves disagree whether to stay in the shadows or trumpet their services.

At the Bunny Ranch, where an outspoken owner has actively sought publicity, several women expressed ambiguity about work that is completely legal, with earnings reported to U.S. tax authorities.

“We live in a world bound by conservative religious individuals who look down on what I do,” said a 29-year-old single mother from Oregon who said she became a “working lady” after a divorce.

Because she would eventually like to work in business or marketing, she uses a brothel name of Olivia Bentley to hide her true identity.

“I’d like to be something else. I don’t want to stereotype myself,” she said. “Do you really want to be known for that? Unfortunately, I don’t know if I would be taken seriously.”

The lure for many women is good money.

“Look, I just made $500 and that was for 15 minutes,” Shelly Duschel, 31, a nine-year veteran of the profession, said during a pause between clients on a recent night. She spoke in a dark red lounge area where visitors choose among the women before going to a private back room.

With half of all earnings going to the brothel, Duschel said she earns about $10,000 a month, but has pulled in as much as $30,000 monthly. Cheaper brothels might charge as little as $100 per visitor, industry officials say.

Despite the good money, Duschel plans to retire soon and concentrate on developing her artistic talents and her personal life. “It’s very hard to have a relationship,” she said. “I’d like to find a good man.”

Prostitution was a staple of the Wild West, but gradually officials moved against well-known brothels. Nevada, which prides itself on a libertarian attitude, opened the door for its counties to license brothels in 1970.

Las Vegas and Reno bar legal brothels, although illegal sex for sale there is commonplace. Nevada counties that allow the only legal U.S. brothels prohibit advertising and set other stringent rules.

“There is a line, a very fine line,” said George Flint, the long-time lobbyist for Nevada’s brothels. “When it really comes down to intimate sexual contact, it has not been and I don’t think it ever will be, for lack of a better word, routine.”

“You’re not going to see states saying, ‘Nevada’s got a good idea there, let’s copy them.'”

Concern about that fine line has caused a rift between Bunny Ranch owner Dennis Hof, who has allowed HBO to film a documentary series at his brothel, and other owners.

“Are we going to expose ourselves like Dennis to the point that people are going rub us out of existence?” said Flint. “The less we are going to have people thinking about it, the longer we are going to survive.”

Susan Austin, the madam at the Wild Horse Adult Resort & Spa outside Reno, agreed. “It will never have total mainstream acceptance,” she said. Hof “is doing it all in the ways that are offensive to the majority of the people.”

Austin, 55, is by no means a shrinking violet. A former prostitute, she says she had sex with as many as 15 different men a day, seven days a week, for six months during the busiest part of her career. She insists that she enjoyed the sex and said the proceeds paid for her son’s college education.

Hof scorns his fellow owners for their low-key approach, and did not even want to be mentioned in an article that included other brothels. “I’m single-handedly trying to sanitize this vice,” he said. “I’m on a mission.”

“A high-profile approach brings higher-quality girls and better-quality customers.”

Many state politicians prefer to sidestep the issue. In an interview, Nevada Gov. Kenny Guinn danced around several questions on the topic before adding: “I’d prefer not to have it at all in the state of Nevada.”

“Politicians tread lightly on this issue; they don’t want it to be brought up,” said Barbara Brents, a sociologist at he University of Nevada, Las Vegas, who is writing a book on prostitution.

At the same time Nevada legislative proposals or voter initiatives to curtail the world’s oldest profession have failed over the past two decades.

“We thought it would be best to keep it out of our community,” said Alan Perazzo, a dairy farmer who campaigned unsuccessfully in 2004 to bar prostitution in his county. “They didn’t want to be told what to do.”

Sociologist Brents said if successful, an announced effort by “Hollywood Madam” Heidi Fleiss to open a brothel catering to women could help win wider public acceptance.

Supporters say state requirements that customers wear condoms and women undergo regular health checks make brothels far more desirable than street walking. Customers are also subject to an anatomical check for signs of disease.

“I used to work illegally in Vegas,” said a 20-year-old woman who uses the name Bunny Love at the Bunny Ranch. “It’s a lot more dangerous.”

The Oregon native seemed to be in good spirits and said she had earned $8,000 over the past week. Her parents, however, do not know about her work.

Industry officials say disease and violence are rare in legal brothels. Flint said that since testing began in the mid-1980s, no legal prostitute has ever become HIV positive; he estimates half a million legal paid sex acts are performed annually in Nevada.

Wild Horse madam Austin does carry carry a gun, but many prostitutes appeared more concerned about how they were treated outside the brothel.

“One of the biggest problems prostitutes face is not abuse by their customers, but the broader stigma from society,” said sociologist Brents. But “I think the trend is toward more openness.”