I have a question about Purebred Dogs?

We are thinking of getting another dog friend, for Diego. Once his problems are solved. Probably a year or two. But anyways, I got to talking with my friend and we currently own a mixed dog, and a purebred Akita (13 years), sadly she has to get put down, next week. She is not a inbred, we got her imported from Japan(from our friend's relative). But anyways, she said that most purebreds are just inbreds now a days. I kind of agree. But is there really that many inbred purebreds?