Well, most people try to go into law because they are passionate about it and because they want to help... well a lot do anyway. The legal system may be screwed, but a world in which there aren't trained people to represent you in a court would suck. It's already pretty bad, because the big companies can afford better lawyers who know the loopholes better than those who act for the little guys. Oh well. Teaching is not something you should do for the money. Too many **** teachers make being a student seem **** without adding one more. If you care about teaching, and you like the idea of helping others learn, then go for it.
Of course, you do realise that the middle ground is quite good. That is, teach music! I reckon the best thing an aspiring musician can do is to study to become a good music teacher, cause that's the best way of earning an income a lot of the time from music, and if you want to teach, what better than to teach what you love?