There is a reason. When you grow up with people around you using imperial units to describe things, you think in terms of it. If you tell me 10 ft., I can picture that in my head, I have an idea of how much that is in real terms. If you tell me 10m, I have no mental idea of how much that is, even if I can convert it. It’s like a language you grow up speaking, versus one you learn later in life.
I do think metric the sole system used in schools, to be honest.