Notice the Manson/Cielo Drive references?

Shampoo just appeared on Amazon Prime giving me a chance to see it after a long, long time. In the past I noticed the political satire (no one noticing who they are about to elect to President), but this time I noticed the eery Manson references - one of the first scenes where Jill says she thinks something terrible is going to happen, she lives in the hills that look like Benedict or Laurel Canyon, and she thinks she hears gunshots at night. Also, George says he needs to take Jill to (I think he says) El Coyote...which is the restaurant Sharon Tate and friends visited the night of their murders. It was like these fictionalized characters were tracing the footsteps of the real-life rich hippie set of the time, Warren Beatty being one of them.