also alot of people try to find meaning in music. Some songs there is others not so much.
mostly i would just say its about listening to some thing that appeals to your mood attitude personality or it just sounds nice. this is why alot of teens listen to music like emo and emo-ish stuff so young so rebellious. it could also be products of environment. people listening to certain musics because they were brought up around them or maybe the music makes a simular connection to there environment like country or the inner city.
there are times i drive with no music on. i just want to hear the sounds of the road and the car as i drive down the highway 120mph.
SOAD has meaning to their lyrics, and Coheat and Cambria has an actually story going through their albums.
However, I agree, some music is just... there.
I agree on the "mood" songs. I listen to the big bass, heavy guitar stuff becuase it appeals to me. But, being raised in 'country'/'middle of freaking nowhere' I also like country.
I'll just stare out of a window when the music isn't on and listen as well... good to know I'm not the only one.