Part of the problem is the tidies that some guys do place basically remove everything from the rear, leaving the license plate tucked up under the seat with a couple of cheap Chinese LED signals (if that). Yoshimura makes good quality tidies that preserve the OE signals and their spacings and provide a clear, properly-lit mount for the license plate. For example, on the CBR650F:
Ninja 300:
And on an FZ8 (similar to what I have on my Fazer):
I think the police are going to care more about signals removed and/or swapped with cheesy, dim and near-invisible junk and plates mounted where they can barely be seen or at goofy angles then the bike only missing a hook-nose "mudguard." On many of the Yoshi tidies I have think most people would be hard pressed to know that the bike didn't come from the factory like that.