Where is juggling shop a thing?

It was in the UK in 1993, about the time the web was starting to take off. As the other commenter says, there was a much wider variety of shops then.

I am not the person you're asking, but they were a thing in The Netherlands at least. Not super common, but they did exist. Typically they sold other related things too, like diabolos, flower sticks, etc. This was a while ago, before Amazon, when there were just a lot more different types of shops. I am not sure they still still exist.