I think the main reason is that the police feel like they have to do something about any complaint of this sort, because they'll be fed to the media sharks on the off chance that something does happen, even if it's some unrelated incident[1]. So all it takes is one idiot making a complaint and the police feel like they must act because that's safer for them and for the department than if they don't.

No-one's going to lose their job or any money over the linked story, so that's the safe option.

[1] "Could the police be partly to blame for so-and-so's disappearance? Here's the story of how our police ignored reports of vulnerable children in the weeks before this horrible event."