Sobored,
Unless I missed something, nobody was directing their rants at you. They were just making general statements. No need to be so defensive.
I believe its illegal to drive with headphones on. The reason for this is so you can hear people honking, emergency vehicles approaching, children playing, trains coming, etc. Not only is it noise pollution and bad common couresty to blast your radio - but its also not safe.
Ever wonder why buses stop at railroad tracks and open the doors? It's so the bus driver can listen for approaching trains. The factor of safety goes up if the driver using his/her sight and hearing.
Being able to listen to your environment while you are driving is a key safety item. Blasting a car radio to the point where you cannot hear your environment should be illegal for that reason alone. (Not to mention the long term health risks to your ears)
I always wondered about those high end luxury cars with all the noise reduction measures. Sure its really quiet in there, but can you hear someone honking at you? Can you hear the ambulance coming toward you?
As for the sticker in quesiton, it looks like Alfonse's stickers available at:
http://www.xterrastuff.com/decals/index.html