True. But the police have a duty to investigate suspicious activity which includes asking questions of any citizen they think may provide useful information.
(and this WAS an illegal detention) based on the asking of seemingly silly questions or the taking of seemingly suspicious photographs.
You'd be right if that was what they based their detention on. I imagine it was his belligerent, uncooperative attitude coupled with suspicious behaviour that gave them just cause.
The author sounds like a jerk to me and this is HIS version of the story. The story in post #16 is something to get bent about, not this.