Most of my friends list is no longer playing GTA:O. When I do pop on and no one is on, I just go into a friends session. Drive around for a bit, then dump out of the game.
But, yes when I have grinded I'm tucked away in an empty friends or a lag switched public session with one or two friends maximum. I don't join random biker clubs, VIP, drug cartels. If I'm grinding I only play with players I know and trust.
I honestly haven't found anyone new that's fun to play with in a long time so my GTA:O is pretty anti-social. Not for want, but it's the reality for me. Hanging out with vulgar 11 year olds isn't my crowd.
Would rather hang with mature gamers.