Well, c'mon metal-addict : What *can* happen, and what likely *does* happen, are two different things. There is always some "ominous sky is falling imminent maximum fine & penalty" that is "on the books". Yet the *reality* is far different.
If anyone can point to instances of "confiscated metal detectors", I'm betting that it's probably someone being defiant that can't take a warning. Or someone night sneaking obvious off-limits monuments, etc.... On the rare (and I mean rare) occasion that someone can EVER point to someone in an innocuous benign spot where this supposedly occurs : That is flukes. That is not norm.
For example: I'm sure that if we scoured the newspaper headlines long enough across the country, we can probably find someone who got his ticketed, jailed, and car confiscated for nothing but a tail-light out. Sure. Flukes happen. For example : I have a clipping of a guy who got a ticket for eating a hamburger while driving (the cop called it "distracted driving"). But notice we recognize these for exactly what they are : Flukes.
So when these rare sky-is-falling posts happen, the WORST thing we can do is to think this means that such instances are imminent. Oh sure, use common sense, but no : The sky is not falling. The worst thing we can do is think this means we need to waltz in asking "can I ?" questions. Lest it merely become a self-fulfilling vicious loop. If someone is skittish (that they might be within an off-limits area), they can study rules and map-boundaries for themselves.