I have talked to people involved in a club/group ride in Australia, but have not ridden with them. There are quite a lot of people involved, and went on serious rides, including overnight camping. They said they join the club/group, but don't pay any money, and people organize rides. Which makes me think, they must not have insurance. They probably wont have any problems, as it is probably not an official identity, and there is no one to sue.