As far as I know, tattoo artists are not considered medical practitioners?
It's surely a gray area, though. I mean, Botox is supposed to be administered by a doctor, right? But I think most places that do it just have a doctor on staff but the aesthetician (sorry, misspelled) does the injections.
To me a glass of wine just sounds like a friendly, nice way to relax before starting the job, but I realize that it could be a serious issue.