So I am basically the social organizer for a large group of friends (mostly from university although we're all working now) because no one else can be bothered. This group has gotten REALLY big over the years (like 30-40 ppl from only 10) which means it can be a pain in the ass getting people to come to places. 

Recently in the past year people have been really into boating events. We'd rent a big boat for a day and pay for food/drinks to be delivered and hang on the water with friends for a whole day. Its a blast but an absolute pain in the ass to plan. I've asked for help but no one volunteers, but everyone is always requesting these events to be planned, so I'm the one putting down deposits and getting everyone to pay me their fair share. 

So this one big issue has cropped up. There are about 2-3 ppl in the group with clear social anxiety or some other anxiety that they claim makes them hard to commit to things. HOWEVER, they are always the first to volunteer and say they want to come to something, only for them to cancel last minute or make me chase them for money for WEEKS. I've tried instituting deadlines for payments but they are the biggest complainers and will post on our group page about it, causing people to ask me to give them leniency because they suffer from mental illnesses but still want to participate. 

Well lately I've just been texting people one on one and sometimes I seriously cannot be bothered to contact those 2-3 people because of the hell they've put me through. But now they've seen a couple of pics on social media and are crying out about injustice and how people like me exacerbate their social anxiety for excluding them. It's 50-50 with other people in the group. Half of the people think I am totally right for excluding people who've screwed me over in the past and the other half thinks I need to have WAAAY more care for these people because they are more sensitive to social rejection. AITA?