I'm surprised to see so many ABers who are usually very keen (and rightly) to object to outrage culture and constant offense-taking who are apparently comfortable with this.
The issue is not whether this stall was incongruous or unfitting for a Christmas market. That is, frankly, a matter of opinion - and a robustly stated opinion like New Judge's is still not much more than an opinion. The issue is whether the people who set up this stall registered that they were going to do it beforehand, followed the correct procedures, and had a right to be there.
If they did - nobody has any right to ask them to leave, provided they aren't doing anything indecent or illegal.
If they didn't - they should not have been there in the first place.
I can see no evidence that the latter is true. And I would venture that if it were true, we'd know about it.