I wouldn't know the feeling. People who run away from such problems should instantly be confronted with them again by means of a higher power. For instance: Parents, teachers, friends, the list goes on.
When a person causes a problem around me, then simply walks away, a big, "What the f*** are you thinking" immediatly pops up. If YOU caused the problem YOU deal with it. That's my philosphy anyways.
So, simply put, tell someone who has reign over them. Tell a parent, even if the first time the parents don't do anything, next time it happens, tell them again. Eventually they'll boil over form being overwhlemed by this consistent problem that they'll have no choice but to act against it. And hopefully in action they'll do the right thing: Make him fix it.
All in all, ranting won't help you; actions will. You can let him win by removing yourself from the problem and just takign it as it is, or, you can inform someone who has power over him of what is going on. They'll make an action and hopefully do the right thing. If not, well, at least he know syou mean business.