"Who wants to have sex with people they don't like?"
Having sex with complete strangers is a good strategy to avoid playing with people you don't like. If you later discover they are repugnant how is it different than the ex bf/gf/spouse you bonked for weeks/months/years before learning they were pond scum?
Rustic's advice is spot on, we've played at parties never exchanging names with our new "friends". But when we're meeting couple on couple Mrs Playful wants to talk over dinner before deciding if play is a possibility.

