Because police have nothing better to do than wait around in pairs for a young lady to drop her panties.
In a version of Yokosuka where there aren't actually any sailors because the ships don't have crews, they probably don't have anything better to do. :)
Actually, these are my credentials...A man shouldn't make excuses.*grab*What is it?
Policemen, over here!
Excuse me, could you hold on?That's enough, you flasher.Still treating me as a boy!?Eh?Come to the police station with us.Wait, why me!?
You should be arresting him instead!!So-sorry about this!!*Drag... Drag...*