I'm not quite sure what you mean. Can you give an example of a group or organization that a student might be compelled to join, but they might have philosophical or religious differences with?
Besides tuition, parking, housing books and other matriculation fees, I can't think of any other mandatory "group" fees.
I don't know if you can "opt out" of Student Activity Fees, whether or not you participate in one of those chartered student group.
Anybody know?