Pitbulls are demon spawns apparently.
Chihuahuas are yappy rats
Small dogs are uppity
The only acceptable dog in the minds of these Lifetime brained weirdos is a golden retriever. These people should not be allowed near any animal
Euros are pretty weird with their dog breed hatred as well
The real answer is that labs and golden retrievers are extremely good natured and thus good with kids. They thus became the default dog for a lot of people. I don't really care for either breed, personally, but that is why
I like labs, I just think all dogs are good dogs.
Their agreeableness also means they get used in advertising and media a lot. It's better to have a calm, easier to train dog on an active TV set. Hence a lot of dog food adds and family sitcoms have a golden retriever as the star pet.