One of the most polarizing, etiquette-related topics in 21st-century America is where people should be allowed to bring their dogs. On the one hand, some have legitimate reasons for having their canine friend go everywhere they go. On the other, there are legitimate issues caused by bringing poorly controlled animals into spaces that don't always accept them. Even dog owners don't always agree on the acceptable boundaries.
This is a debate that was once again revived when a man filmed himself calling out a woman who had put her dog in her shopping cart as she checked out her groceries. A lot of people thought he had gone too far in criticizing an animal that wasn't causing any problems, but others thought that he had a point about what spaces should be dog-free. So long as many animal lovers want to bring their pets everywhere, the argument is going to continue.
