Re: mafia elitism... yes it exists, and for good reason. playing in noob heavy games makes me pull my hair out. I signed up as replacement in some noob-heavy games and quickly realized that's why I dont' play them. I don't think games need to be invite only, rather game mods should have open signups and handpick players to make sure the majority of players are experienced, not just take whoever signs up first. Sure have some noobs in there, so they can learn and prove themselves to the other players. I think Andy uses a 3:1 ratio, but 2:1 would probably be ok too.
Also, gamemod elitism exists as well.
I have my list of mods I'll play under and it's pretty short. when I get down to zero games, I often branch out, as I did recently. helps to meet new players that way too.