I blame self absorbed absent parents and the lack of good ol' fashion ass whoopins.
Not putting your hands on your kids butts now and again is the problem. I didn't screw around when I was a kid because I feared my dad and what he would do to me if I did. My kids don't act a fool because I lay my hands on them when need be. Now they want to give kids time outs and that kind of crap. Put your hand against their butt when they screw up, you'll see things change.