Yes, the sixties and seventies definitely had a dark side. Amid the free love, drugs and draft, the counter culture was also experimenting with the occult. It may have had its origins in previous decades, but there can be no denying that there was an occult explosion overtaking America and Western Europe.
From an excellent article at The Den of Geek:
The 1970s was verily the decade of the occult, to a level of national fascination (at least in the UK) that is hard to understand if you weren't there. Tarot cards fell out of Christmas crackers; young children were turned onto drugs early by the latex fumes from werewolf masks; we were all building those Mattel Draculas and Frankensteins (more glue-sniffing opportunities) with The Carpenters on in the background; Hammer films seemed to run on a loop at weekends...
Naturally, the cultural trend was reflected on the bookshelves. Not since the Victorian ghost story craze had occult related fiction experienced such a mass appeal. Rosemary's Baby and The Exorcist were bestsellers in the States and Dennis Wheatley's occult fiction became hugely popular in the UK. In addition, hundreds of other authors flooded the market with their versions of the occult drama.
Below are couple mosaics I made from paperbacks from this period. By no means does this come close to scratching the surface of the occult phenomenon that occurred. (click to enlarge)