Well you don't have a lot of data to go on but... I'd say that charity rides are more dangerous than club rides.

It's all abotu riding with experienced people... I've hooked handlebars with guys on club rides and we just coasted through the corner and unhooked. No one freaked out. I ride with guys who know how to ride predictably, point out road obstacles, etc.

Now imagine riding shoulder to shoulder with people that have little group riding experience... it makes me shudder. I'm not saying that charity rides are bloodbaths or anything but when I've got 5 months of training invested in a season so far I'd rather ride with a club then get taken out in a charity ride...