Re the Beach Boys/Charles Manson notable.
http://centerforaninformedamerica.com/inside-the-lc-the-strange-but-mostly-true-story-of-laurel-canyon-and-the-birth-of-the-hippie-generation-part-i/
Tl;dr: Pretty much the entire hippie scene (Jefferson Airplane, the Doors, Beach Boys, Monkees, Zappa, CSNY etc.) was a bunch of kids from military and/or elite families, most of whom couldn't even play their instruments (there were some talented musicians involved, e.g. Zappa, Neil Young, one Beach Boy, Phil Spector). Suddenly, for no reason at all, they went off to Laurel Canyon together, a place with no music history. A bunch of suspicious deaths, including a small child who fell off a roof and his parents went out dancing that night anyway. Jim Morrison's dad started the Vietnam War.