Perhaps we're overthinking the matches thing. I haven't read anything about the condition or age of the matches (were they all new, freshly burned matches, or were they of differing ages?). It might just be that a pipe smoker frequents this bench. Or any smoker(s) who doesn't carry a lighter for whatever reason.
The matches might not be evidence at all, which may be why they weren't taken by the police.
the matches don't matter much now...news was on some local channel(according to PhiKap and one other poster) that the kids roomate was Pakistani and he can not be found! That's all I need to know folks. Don't mean to sound like I am profiling..but I am. This story is not over.