What Matt Derrick said is true if you're responsible it's not a problem and they're good packs its worth being careful as well you know it's full of your stuff which you probably baked so you'll be cautious anyway.
I do still think it's more likely to get stolen especially when it still looks new, but I frequently leave my pack stupid places, like I like to swim and I leave it sit on the beach unguarded.. even if I saw someone taking it I'd never get back quick enough, I also let it go under buses you know that have several stops so someone could pretend it's theirs, in car trunks, stash it up a tree or in a bush or behind some junk or leave it at the entrance to a supermarket or whatever store if asked. So that's basically why I don't buy another.