Ok well here's the deal with those assclowns. The only reason they thump their noise at the stop lights is to get your attention. The logic behind it is that they honestly think that it makes them cool. I know cause well...I used to be one of those assclowns. Not proud of it, but its true enough. I had the total package custom install and enough wattage to deafen myself and the guy in the car in front of me. But you grow out of it.
Anywho, if you really want to piss them off, dont give em what they want. Dont look at them. Seriously. SERIOUSLY. Even if your walking by them in the parking lot on your way to your car, and their bass is making the fillings in your teeth hurt while it curdles the milk in ur grocery bag just stroll on by paying them no mind.
Just dont give em what they want. Christ, stop in front of their "ride" and yawn, LOL.