I don't really see a double standard. Pop singers & groups often present a squeaky clean image (like Whitney Houston) and then when it's found out they aren't like their image they're seen as a phony or hypocrite by some people. Rock n roll from the beginning was seen as rebellion for teenagers and young adults. The slogan is "sex, drugs & rock n roll" and groupies have written books about sleeping with members of rock bands. Many rock songs are about doing drugs or was influenced by drug use like psychedelic rock and stoner rock. Same with ganja in reggae music. Stories of rock singers dying of an overdose are presented as part of their story like the 27 club (Jimi Hendrix, Jim Morrison, Janis Joplin, etc). People laughed at Ozzy Osbourne snorting ants or biting a bat, it's considered cool by some of his fans. Donny Osmond gave an interview once and said that when he was trying to make a comeback in the 1980s, his manager at the time told Donny he should set up a publicity stunt in that he get arrested with drugs to be seen as cool by the MTV audience. Donny didn't do drugs and said he didn't want to present that kind of an image that would hurt his family. Donny didn't want success that bad.