How cold is to cold?

You did the right thing.
Typically, they say when it gets below zero or the wind is bad. Your supposed to put them in a shelter or bring them in.

Yes, depends on the breed and tolerance of the dog. We had outdoor dogs growing up, they had their houses (never chained). We lived in the Upper Peninsula of Michigan where it frequently gets below zero. On really cold nights, my dad would put them in the workshop where he had a woodstove. The breeds were a lab mix (long-haired) and a husky mix. Our dog now is not cold tolerant. I am more careful with him. Our pup spends a lot of the time in the car running errands. He just sleeps when we leave him for longer periods. He absolutely loves going with us and is bummed when it is too warm. I would not leave him without a thick blanket if it were in the 30's. I would also not leave him long in that temp.

I think the better question is what the hell was he doing with a dog in the car while at the bar? I can understand running into the store to quickly grab something but really, you had to stop and have a drink before going home?…but I digress. I am pretty sure it depends on the dog. Obviously young, bigger dogs with full coats deal better with the cold. Growing up my family only had inside dogs.