I personally would not. I agree with the other posters that there are way too many dogs in the shelters that need to be adopted, so I wouldn't have the heart to buy a dog, especially not one that cost that much money!
I guess I could see someone buying a specific breed under special circumstances. For instance, I know that Labradoodles are highly desired because they have excellent personalities (very smart, loyal, and mellow) and are hypo-allergenic because they don't shed, making them desirable to people who are allergic to most dogs.
I'm sure there are other special circumstances as well. I bet there are some people out there that just don't care about (or don't think about) dogs that need to be adopted, so they go ahead and get their custom dog anyway, which is kinda sad.