Yes but the point is she was ok with it. Which is not what a large population of females feel like...
You can't sue customers for sexual harassment. Anyone working in a customer-facing position must be willing to put up with poor behavior (of all sorts) on the part of customers; it's pretty much part of the job description. If it gets bad enough you fire the customer, but in the mean time you just get the work done, take their money, and be ok with it. The only thing worse than annoying customers is no customers.
I've been in that position and I felt the same as the author in this particular regard. Obviously sexist clients made me angry to deal with in the moment, but they're the same as any other type of asshole when you come right down to it. And sleep time is too precious to waste thinking about assholes.
I still loved my job and coworkers and would recommend it to other women. Sure sexism exists, but it exists everywhere. Why miss out on a good gig because bad customers exist?
I was waitstaff once. I quit on day 2. I am sure if you surveyed most waitresses, they'd say they don't lose any sleep over the kind of sexual harassment faced from customers but that's survivors bias in my opinion.
Anyone who did lose sleep, like I did, quit like I did unless of course they had no choice but to go on because they needed the income.