I detest screaming. Some metal fans link me some videos for me to listen to (although I am not much a big fan of it), and some genuinely nicely sounding songs just feel ruined by the screaming.
I don't know, I guess in some cases it compliments the song, when the rest of the song is 'noisy' (for lack of a better word), but when someone puts a more 'melodic' sounding band behind the screaming it feels like a terrible conflict of sounds.
You are right, it is an acquired taste. I think ALL sounds are an acquired taste. Once you listen to something intently you will find it more enjoyable to listen to. I detested dubstep, for example, but the more I listened to it, I have developed a tolerance for the things I dislike about it and started to notice parts of the genre that I liked.
And It's the same for pop, jazz, metal, electronica etc.
Screaming is not a BAD thing. It's just another form of expression, and it takes time and effort to work well, like singing. Good singers will be able to make all sorts of sounds with their voice. Good singers are able to scream/growl AND sing well.
I don't know the effects of continuous screaming may have on your voice though, but I think it's a fun thing to play with now and then, just to widen your voice range and make it more flexible. I doubt it will do damage in the long run if you're doing it properly, warming up before doing it, not smoking/drinking etc.