14,000 years of being domesticated to serve as companions for humans is the inherent reason that works for me. Cows or pigs don't have the same history of domestication to be companions. Dogs share a special bond with humans and a special place in our society. Rightly or wrongly, and admittedly cows and pigs suffer to certainly the same extent that any factory farmed animal suffers, dogs serve a different purpose.

Given this history and bond, to eat or put dogs in danger is in my mind almost as morally objectionable as putting a person in grievous danger against their will.

In Western society. In Polynesia dogs and pigs (which are just as intelligent and social, IUUC) where both kept both as pets and as a source of food. https://en.wikipedia.org/wiki/Dog_meat#Polynesia

Dogs got personality, personality goes a long way.

Have you spent much time with cows and pigs? They have just as much personality as a dog.

Pigs do have personalities, you usually just don't spend enough with a pig to get to know him.