I guess once again, it depends on where you live. Around here there's always another route to take to get where you're going.
Some of these groups are riding "in memory" of someone. Or for some charity. I don't want to bust in and out of a group just because I'm in a hurry. I'll just find another way.
Then there's still a few groups who would think nothing of running you off the road and kicking your ****** from here to Calcutta just because.....
Let your conscience be your guide.