a current trend is to keep Toy Dogs, I have seen old folks, and young single woman walking around with Tog Dogs in their hand or bags. By Toy dogs I mean small little doggies. The support service for such pets seem to be booming with grooming services and mobile pooch baths.
Locking up Little Dogs in Cars with wound up windows, (also children) when running off to get some thing is not a good idea i would say, even if you intend to take only a few minutes. You never know what might happen.