I ride with people that are slower than me. But we have such a fun time I don't want to "drop them". Nice thing is, I can ride 15-20 miles with them and then bomb the last 5 miles and no one gets their feelings hurt.
To ride with people my speed I'd have to jump in with the "slow" group on the club rides and they take themselves too seriously...ie: no fun to joke around with.
I'd rather ride with fun people