For example, say a boy and girl are standing on a doorstep. Now let's say he kisses her. In one scenario, she kisses him. In another scenario, she might slap him as a consequence. Not all reward and punishment is quite this obvious.
Reward can be as subtle as the feeling of elevation that comes from doing a good deed.
So, back to our busy store clerk example. I've been told that bullying is the number one social issue in children's lives today. They tell me they have a conflict education program. Bullying is indeed a significant problem in many children's lives. Instruction in karate, along with an accompanying conflict education program, can be a good option for some children.