Judging from the context, it seems to me that ので in the following sentence means "in order to", similar to のに, and not "because of". Can this be possible?
Also, I don't get the general meaning of the second part of the sentence, in particular who 勝手に relates to, the person in question or his followers? Here's my attempt:
He is considered the leader of the extremist faction, but that's not his intention, he has his volunteer followers around simply in order to avoid any inconvenience.
Thanks for your help!