Why is it that I seem more attractive to women when I'm driving my car or wearing my sunglasses?

I'm 19. I've had this happen to me quite a lot now. The question is self-explanatory really. I'm only ever attractive to the women when I'm driving my car or wearing my sunglasses. I remember once I was walking down a street and the sun got a bit bright so I put on my sunglasses and then these young women stared at me (they didn't stare when I wasn't wearing my shades). Also they only seem to notice me more when I'm driving my car, cruising down the street with my window down and the stereo turned up loud. The young female students can get a better look at me in my car when I'm driving to and from college and they get a good look at me in my car because I drive slowly in the car park because the speed limit is 5 mph and that car park is a minefield of speed ramps so if I exceed that I risk damaging my car and having my student parking permit revoked. Anyway, why I more attractive to young women when I'm wearing sunglasses or driving my car than I am left to my own devices? This fascinates me. I don't argue with it. I just go with it and drive and wear sunglasses whenever I can.