I would have been amused by it in hindsight, but rather rattled as it was happening.
It is a (minor as I see it) abuse of power, but I think it rated higher on the rudeness scale. There should have been ways to catch your attention and ask you to pull over without raising your hackles that you were "in trouble for something" and wasting at least a minute or two of your time before you found out if it was OK for you to just get where you may have needed to be.
I haven't had a cop ask to see my bike, but I am constantly having stop light conversations with neighboring cars about the bike and, for some reason, I usually end up doing something bone-headed right after it, which I'm pretty sure is a selling point for "Oh, look, even if you are a total spaz, you can ride that bike". I got stopped by some pedestrians waiting for a right turn arrow in SF one evening and when they noticed my light had changed and withdrew their conversation I then proceeded to completely botch the launch into the turn and ended up hitting the horn.
"No problem, you're welcome! <cartoon fumbling sounds> <HONK> (blush, ride away quickly - how the heck did I hit the horn button??)"...