I agree with Candybar. At this point, write down all the expenses and what it cost and show him on paper so he can see it for himself. If food is a problem, buy your food separately.This should have been done in the beggining.
Since you're pretty much doing this for poll purposes... your roommate is an irresponsible, selfish and a leaching roommate. Where exactly does your roommate believe that these things come from and are available? Should pay half
Well put a password on wifi or computer so he can't use Internet, I'd lock away anything that he hasn't payed for, as for electric and other utilities tell him straight up, either pay half or raise his rent or he's evicted.