He does seem to be taking advantage of you and I don't see a point of remaining his friend unless, of course, you are a career criminal who does a lot of white collar crimes or something of the sort and need contacts in the system to get you out of trouble if you were caught. Of course if you are, don't tell any of us here

If you are on the right side of the law and there are no other benefit of paying him more other than to keep his "friendship" then I would break it off.