That kid's seen too many movies about breaking glass with bare hands or arms without getting a scratch. That's Hollywood glass. The real thing almost always inflicts cuts and I personally know of one person who died after walking through a sliding glass door due to rapid blood loss.
Note that his accomplice is wearing a backpack. On unfamiliar young males wandering about in residential neighborhoods, it's the official uniform of a guy who's looking for something to steal. It never fails.