I know many people who listen everything but radio music. I rarely listen radio, unless is a rock station. And I actually watch a lot of vídeos on youtube. Surely I'm not the only one. Maybe radio comes in handy to some people or maybe they like that música that's been aired in continuous loops over and over again.
Maybe not everyone has heard of Vevo or I don't know other ways. Besides, how do you know these people you talk about only listen to the radio. There are a lot of people. Like myself, I rarely ever listen to the radio, sometimes when my sister is only on the air, I also rarely listen to música on the internet though. I usually just listen to what's on my ipod. And as for these other people, who knows.
I only listen on the internet, or download the MP3 and listen to it on my phone or Foobar. I am guessing because they don't know what to listen to so they listen to the radio. I mean....I would do it that way if I liked hearing música constantly.