It's probably for the better they're taken down. In California, and perhaps NY and NJ, too, the status shows up on your DMV records, so when a cop runs your license or your plate (and I presume plates are scanned and run automatically), they'll see the discrepancy immediately. So someone is just asking for trouble by using fake stickers, just like if they went around flashing a gang sign when they're not actually a member.

That in itself blows my mind, why on earth should someone see your membership in this order? It's not a LE agency, and in many states the FOP allows membership for retired cops.

I do agree with what you're saying, though, but the issue to me is why that's even something that should show up when your plates are run, "Oh, you're a cop somewhere, or used to be".