Sometimes I just shake my head...other times I just slap it...:S
Why would you want your plate to be obscured?..:h These same people that ask these questions are the ones that bit$h the most when their trucks get stolen and the cops can't find them.
In answer to your question, yes, I would and have stopped and depending on attitude you might get a ticket or a warning. Second stop for same violation becomes a misdemeanor. Same answer for those having the "Look at me, I run red lights" covering on their plates thinking the cameras can't pick them up....Dennis