You don't have to like the system in their car. But in the same right, they should respect your right to not hear them. My car is pretty loud i must say, but i always turn it down when i am in a residential area. I only run it full out when i am on highways with the windows open. If its any consolation, they will be the ones with hearing damage in a few years (i already can tell i got hearing damage). Loud cars seem to be a dying fad in my area. There used to be a jeep that came by that would rattle all the windows in my house from about 100 feet down the street. There just doesn't seem to be the ammount of them around.

For the cars with loud exhausts, they are annoying but NO WHERE near the volume of a harley. There should be some noise control on them