Yes, but not dangerous.  How you feel about it is not the issue.  The protection of prostitutes is, and for the word "prostitute" you can substitute any word you like for women and men who offer sexual stimulation (of varying kinds) in exchange for money.

What I see is that where a moral opprobrium is placed on an activity, that activity immediately becomes more dangerous.  After all, there is absolutely no need whatsoever for anyone to wander around Amsterdam's red light district.  It is clearly marked on the city maps, so those who don't like that kind of thing can avoid it, and it is nowhere near the concertgebau...

Don't fight forces, use them R. Buckminster Fuller.