Basically, the idea is that the lives of rock stars are in their bigger part those three things: having sex (with fans), using drugs(often illegal ones), and performing (this is what the rock and roll stands for).
1) Elvis Presley. Died of drug abuse.
2) Guns and Roses. The guitarist Slash nearly died of drug abuse.
3) Queen. Vocal Freddy Mercury died of AIDS after being infected by having unprotected sex.
2) the reason why grunge kicked out hair metal
3) the reason why everyone hates emo
2) All hair metal was doing was following the unneeded "sex, drugs, and rock n roll" trend, and Nirvana knew that there was more to rock than that, so they kicked the hair metal musicians' sorry butts to the curb. Unfortunately, this trend is making a comeback, and it really needs to die!
3) Sex, drugs, and rock n roll is a stupid trend, and emo is actually meaningful than all the songs that follow this trend. Emo cares about the music; the artists that follow this trend only care about excesses, and that's what emo haters expect emo artists to sing about, when in reality, emo is far deeper than this moronic hard rock. Anyone can do this trend; few people can do emo.