Who let the dog(s) out?!

We've lived in our neighborhood for about 4 years, and our neighbors are on their fourth dog. I don't know what their problem is.

This time, they left a very small black lab puppy (I'm estimating 4-6 weeks old) outside in their fenced in yard while they went away for a few hours. It wasn't terribly cold, maybe upper 20s to around freezing. But he seemed really young to be left alone, and he managed to squeeze through a hole in the fence and came crying over to our house. I felt sorry for him and kept him inside for a bit. We put him back outside, and I think they finally came home and took him inside.

Irresponsible pet owners cheese me off.