Thing is, for some of us, it's not snobbery. It's knowledge.
Not the UK, the US, but I had an experience with a guide in an historic house near DC - you could only do a guided tour, so had to stick with your docent. In the hall, she pointed to a series of prints and emphasised how important they were to the builder of the house, because they were of his home, Carlisle, in Scotland 
I piped up (idiot that I am) and said, "Oh no, Carlisle is in England. I'm from round there and it's very important that it's not in Scotland. We have defences against those Scottish border reivers." (a joke that whizzed straight over her head)
She looked at me as if I had just landed from outer space, and said "No, Carlisle is in Scotland." I didn't push it, but just asked questions about the provenance of the prints, and how they were made. None of which could she answer.
So OK, she wasn't an art historian. But to treat an English visitor from north Cumbria as if she doesn't know her own history ... Hmmmm