On a recent Wednesday evening the small, tranquil four-stall bathroom at the “21” Club in Manhattan was free of patrons. Still, Pat Velasquez, 72, dressed in a black blazer and matching pants, and black and white printed silk shirt, stood by the sink, a white paper towel in her hand, ready for someone to enter. Eventually Mary Garrett, a first-time customer, did.

“I’ve not been in a restaurant that has an attendant in a long time,” Ms. Garrett said, looking pleasantly surprised. “The bathroom attendant is a thankless, antiquated job. You’re paying an employee to do something no one understands. This is very genteel. I can’t believe they have one.”

Ms. Velasquez makes $15 an hour and if she’s lucky, takes home an additional $15 to $20 in tips during a shift that lasts six and a half hours. (“21” also employs another attendant, Roseanne Huschle, who has been with the restaurant for 20 years.)

“It’s not easy, but it’s worth it. I’m a people person and you get to meet everyone — tourists and regulars,” Ms. Velasquez said. “The bathroom is the main part of everything. People cry in here. They lean on my shoulder. I’m like a psychiatrist. Sometimes they’re drunk and throw up. Or they come in and make private calls. Or they want to smoke and are disappointed that I’m here, so they can’t.”