Didn't your mother ever teach you that something isn't necessarily a good thing to do, even if "everyone else does it!" Even if "half the US" bribes their children, that does not make it a good thing, especially if that bribe interfers with everyone else around the child.
Secondly, I suspect your statements regarding your children. As the poster above stated, you sound like you are 13. If you are truly an adult with children, I pity those children. How on earth are you going to teach them to speak and write properly if you can't do so?
Many children don't act badly in the grocery store or the mall. Perhaps you should spend some time observing the quiet children in the background. It's the few bad apples that make all children look bad. One thing that you may notice if you spend time with families who have well behaved children is that the children's behavior isn't moderated by bribes. That's not to say that they don't get special treats once in a while. But bribing them into good behavior does not work in the long term. Well behaved children happen when children are taught proper behavior, not when they are temperarily shut up with a toy.