briancraig said:"Music taste is formed in early adolescence." I don't really doubt this and even though I once gave an example of how many people I grew up with in Memphis who liked AOR as teens but today almost exclusively listen to country now that they are in their 40s, your explanation for this made sense.
This is one of the best researched areas in the social and behavioural sciences. One's base taste is formed in early adolescence, and simply progresses or branches from there. The CHR oriented early teen may branch to some form of rock, or to a lighter form, such as AC or even modern country depending on environmental factors.
Among Hispanics, a person who grows up hearing what in the US is called (mistakenly) Regional Mexican music forms, like ranchera, will stay close to those forms... they won't suddenly start liking alternative rock in their 20's, nor will they start liking rock or alternative in Spanish, either.
However, I still feel sorry for people whose music tastes are frozen in early adolescence. How sad not to constantly be discovering new genres and artists. I know I'm not the average music consumer as anyone who owns over 6000 records isn't indicative of the public, but still how pathetic to only like at 40 what you liked at 14.
Very few people have the curiosity about music that some posters here have. Most people like familiar songs, familiar artists and familiar styles... so they follow a well defined road as they mature that is closely linked to the early life experience of the person.
Also, there seems to be a link between musical diversity and higher educational and income levels, and I have seen several studies that show greater interest or acceptance in such people. Of course, such people tend to travel more, particularly internationally, and often know other languages and are not threatened by other cultures.
I think you could state that a percentage of that sort of person is not going to be terribly devoted to radio, and will seek out alternatives to satisfy their needs.