The melodramatic emotions elicited by the music puts them in a temporary stupor. An escape from the real horror of life as it is organized in modern society. And from the look of things, top forty music is not just an escape, it's a Diaspora. Teens can't get enough of it. Alanis Morrisete, Top Forty bubble-gum queen, is a millionaire.
Teens are easy targets for record companies which have a captive audience.
There's nothing to listen to on the radio except Top 40 crap most places. Good stuff sneaks through, but doesn't have very good wattage. Hopefully the Net will make autonomous programming a wide-spread reality. Until then, happy bubble blowing.