I just dont get it

On Saturday night we went to a parade and on the way home we were on our cities light rail train. It was FULL. we get to a stop and this family of 6 sees the train is full and decides to cram on anyway, making the train in that area go from crowded to claustrophobic. (it was the end of an event and trains were coming less then every five minutes) Last night we were driving home and we see this chick on the side of the road that is on her phone and obviously pissed off, she starts kicking the bus stop bench and then proceeds to jump on it and destroy it. We were at the park yesterday and I was amazed at the amount of litter on the ground.
I guess I just don't get why people think they are so much better then everyone else that the general rules of society don't apply to them.  People who Jay walk and stop traffic a half a block from a cross walk, the idiots that think that some how the huge "no parking" signs in front of stores don't apply to them.
I am a rule follower. I go in the enter door and use my blinker because I know that things like that are what make society a nice place to live.
Do these people not care honestly? Or are they clueless that they are being an asshat. Is it the rush they get for not following the "norm"? Or are they so wrapped up in their self importance that they think the rest of the world is here to pick up their cigarette butts.
I don't know where I am going with this, I just get sick of feeling like the world's mom. I signed up to pick up after my kids and deal with the self centeredness that comes with children, but I'm sick of having to take it from grown adults that should know better.