It's the 24th century, communal showers shouldn't be a big deal along with communal nudity.
They should be largely rid of most puritanical views on the body and sex.
They must have cured all the diseases as well; was it this episode or the previous one where they made a reference to all the adventure on the Enterprise with Riker catching space diseases and all? (A joke I was not expecting, they did it, and I was on the floor rolling once they mentioned it.)