I'm a dog owner and a dog lover, but OP is right that many people who own dogs have gotten bad. The sense of entitlement people have is out of control, and it extends to their behavior with their dogs. I, too, have seen people take (usually little) dogs into restaurants. Owners sometimes don't notice, but even when they do, I think they just wait to see if anyone complains. I've also seen all manner of dogs in grocery stores. People with legitimate service dogs usually have vests on them, not just to make it clear to business owners, but because they usually don't want people petting and distracting the service dogs when they're on duty. That pug on the bedazzled pink leash wandering through the produce aisle probably isn't a service dog.

I've seen it several times on the east coast of the US. So I'd be kinda surprised if it doesn't happen elsewhere. Same with stores, I assume it's usually a case of it being against policy, but the host making minimum wage not wanting to deal with the "THIS IS MY SUPPORT ANIMAL" ridiculousness. I don't see it often, I just think it's a good example of this narcissistic attitude.

No kidding, that's hardcore against public health rules in most of the USA.