Why is bullying socially acceptable?

Why didn't an adult teach me when I was young that bullying isn't acceptable?

 I had a friend who walked funny and a used to tell him he looked dumb. and when i was in a twenties and had a few years of driving experience I tailgated other drivers, I cut them off if they annoyed me, I honked, I flipped them off, and if I couldn't get past them on a four lane road I sped up and slowed down just so they had to focus behind them as much as ahead of them.

I've been bullied, when I was 10 a 15 year old guy followed me around the playground and called me names, spit on me, and threatened to beat me if I didn't leave. I've been beat, I've had guys throw fist sized rocks at me too. And much Too many incidents to list.

I don't bully on the road anymore, but nether do I screw with people who want to speed. And no I don't fucking pull off the road they have to pass me. Safety is their responsibility.

When I was brainwashed by Sunday School I looked to Jesus as a role model, believing that all people could treat each other with respect to ensure world peace and harmony- I thought Jesus was more like Buddha.  As it turns out, expecting everyone to be nice to each other is a way to get yourself on the lowest rungs of the social ladder- no respect or admiration among peers, instead earning labels such as tool, pushover, fag or the archaic milquetoast.  As it turns out, society runs on competition and conflict, from business to romance to politics- everything is based on not sitting around and hoping everyone gets along.  It's taken me a while to try to become a real asshole, but I realize that's what society needs.