I don't dislike mixed breed dogs; I dislike breeders who sell mixed breeds at purebred prices claiming the offspring will have hybrid vigor and the best traits of both parents. My own father fell for that nonsense and now owns a labradoodle. The dog is fine - again, I have no problems with mixed breeds themselves - but he massively overpaid for a mutt who sheds just as much as any dog because he and the breeders had a basic misunderstanding of why poodles are described as non-shedders. Or else labradoodle breeders are simply knowingly swindling their customers, which is something I won't rule out.
I also have my own opinion on breeders of pet-quality pure breeds who charge as much as breeders who are mindful of the traits and characteristics they're breeding into their dogs, but I won't go into that particular rant right now except to say I'd sooner pay top dollar for a mixed breed that was carefully and selectively bred for by someone who understands genetics and purposeful breeding than pay the prices people are asking for their pure bred, pet-quality puppies.