(it's also not summer yet)
Well. Neither breed is well represented here. We Doberman people get a little edgy when people portray our breed, even as a misbegotten halfbreed, as vicious and unbalanced and a loose cannon. Of course, Chihuahua people could very well the same way. I've never personally met a well bred Chihuahua of appropriate temperament; I'm sure they exist, but they're a breed that's suffered dearly as well, due to movie popularity, negligence, and overbreeding.
I've never taken Elka to a dog park, nor will I, but the peoples' extreme SAVE YOURSELVES! reaction is an exaggeration of something I'll see just walking her down the street. They cross the street. They lock their car doors. They get back into cars, or go back inside. I haven't seen (heard?) anybody scream at least, but it's really very strange, to me. But there's no accounting for what a stranger and their dog may or may not do, breed notwithstanding.
Then there's the salesperson who's all "LOL, designer breeds! Golly, it's the ticket for when you can't choose!" Personally, I don't think people are going to take dog advice from a car commercial (and if they do, it should be from those Subaru commercials where the dogs have seat belts. Srsly.) They aren't going to run out and slap two breeds together because "why didn't I think of that?", from the pet store or otherwise, and I really hope I'm not wrong. But really? I have to give people some credit. They're not that easily influenced. Dog breeding might sound easy (put a boy and a girl together!), but the mechanics of it are involved, expensive, and gross. And if you're going to be a responsible breeder who titles and health tests....well, you know the commercial's "advice" is bull anyway.
I can say "Okay, it's kind of funny. That's clearly a freaky not-real dog. The couple clearly decides it's really not a good idea, and they clearly rescue a dog from the shelter in their swag Audi with the clearly spelled out message COMPROMISE IS BAD. The end." Really, I think Audi dropped the ball in not using "German engineering" in conjunction with the Doberman, but did VW do that already?
Bottom line: don't buy dogs from pet stores, don't randomly create designer breeds, rescue if you want, get a car you're happy with.