I don't know that you MUST pay him. Some parents do it because they want their children to learn how to earn money.
I, too, don't think personal jobs like brushing teeth need to be paying jobs. One needs to do those things no matter what. Perhaps you could make some sort of chart for getting things done at night and in the morning. He could put stars on it to show that they were done at the right times. Some youngsters look at that as a reward in itself.
It's sometimes of question of learning how to work for money versus learning how to work for the family. Which one do you want to teach him? He needs to learn both. In a family, everybody helps. For instance, you don't get paid by him for fixing breakfast; that's part of your family job. Daddy does (what?) not to get paid for it but because that's part of his family job. Your son's family jobs include making his bed, picking up his toys, and (fill in the blank). It's good to learn how to work as a team at home.
On the other hand, three of my granddaughters (the youngest is a year older than your son) each have a chart of things they need to do during a week. When they have done those things, they get their weekly spending money.
So you want to decide what your focus needs to be right now. When he's a little older, of course, paying jobs will become a more definite focus.
P.S. Just found this a minute ago - maybe it will help:
http://www.focusonthefamily.com/parenting/parenting_chall...