Funny reading the comments of people who don't actually live here!
Yes it's a cultural thing, but that has been developed by the last government. There is a fear of cameras everywhere, if you carry one on the street taking photos of people you are likely to be threatened by thugs, (the level of threat does depend on where you are) but no public / private place allows photography and if they catch you it's vigorously surpressed. Police even caught an MP taking photos in London and questioned him under the anti terrorism laws.
This incident catagorically was not a missunderstanding, it was quite deliberate on behalf of the shopping centre security, and the Police, both referred to a notice which apparantly banned photography. The security guard did act illegally, requesting that the images were deleted, but unfortunately our police are so dim witted they are 'barely literate'* and most haven't got the first clue even about basic law let alone specialised stuff, worse they will not listen to people who know better than them and refuse to accept they are ever wrong.
In answer to JonJT there are issues with English migrants living in large communities in France & Spain, where they refuse to learn even the basics of the language, or integrate in any way.
*Tom Winsors review of Police for the Home Office