He explained his point harshly, yet completly correct, then rode off.
Being correct is only part of it, you have to word what your saying properly so that the other person will understand and stop. If you just shout cusses at them and insult them, they'll only think about you shouting and cussing, instead of thinking about what they did wrong.
Doesn't matter what his age was, the point was delivered, and he was gone before she could do something stupid in defense.
I agree that riding away was probably a good thing to do, but age is always a problem. Adults tend to look down on teenagers and kids, and they often think of us as irrational and hot-tempered. The way he went about speaking to this woman probably only made her believe the stereotype further.