Idk, am I naive to think a good FAQ should help to some extent? Not like on Couchsurfing “hey guys stay safe and help with the chores”, but detailed and with examples (and not too serious, so people don’t close it after the first paragraph 
). And when smb sends their first message or request, there can be a reminder, like “we have an FAQ, you might want to check it out”.
It’s probably not so much for “keeping the creeps out” but rather for new users to understand what it is all about. Can help as well though - by showing people how to choose a good host/surfer and how to write requests (so good hosts accept them).