Like all teenagers of the early 70s I LOVED Grand Funk Railroad. Especially their live album. Yes, Mark Farner is probably the worst guitar player in the history of music but Mel Shacher is THE best bass player in the history of music.
Their music is so silly. But, it is very danceable, happy, and fun.
Not only did they not sing about drugs, almost all their live shows were interrupted by Farner giving a 'lecture' about drug use.
I will never forget a day when one of the elders chose to grace our family with his presence, and I was very happy that he and his wife were visiting our little apartment, and as he walks in the front door he sees Grand Funk Railroad Live on my mother's stereo and he picks it up and sniffs like he smells something bad and says "This looks wild, this will have to go".
I asked why and he mumbled something about drugs and I said "But the band members dislike drugs and tell the young people not to use drugs", then he switched to the sex excuse, and I said "but their songs have no sexually explicit lyrics in them". This then turned into an oratory on "rock" music altogether.
I never did figure out why God hates Grand Funk. Don't you just love that name?