Vanity or curiosity?

The last few days I have noticed vehicles with bird droppings on their doors. Turns out there is at least one Song Sparrow that is infatuated with its reflection! 

I tried to catch it looking in the mirror but it stayed on the far side of the truck. I could see it drop to the front of the mirror, sit for a couple seconds then move back to the top. Although it did not go to the other mirror while I watched, there was evidence it had been there!

This truck has only been here about 2 hours. Yesterday, a van had been parked over night and it had a much larger amount of droppings than this one! I may check on it in another couple hours!