The Bloodstained Lawn (1973)

This is a hallucinatory, somewhat drug-abuse themed horror movie which is kind of an Italian version of a "Coffin Joe" film like "Awakening of the Beast", and with the same subtext of social commentary. It's about a group of aristocrats (a husband, a wife, and the wife's brother) who are literally draining the blood of the people. They pick up the dregs of society--prostitutes, homeless hitchhikers, etc--and take them back to their isolated villa with its weird crimson-colored "bloodstained" lawn. They feed them drinks and weird drugs and engage them in wild orgies before hooking them to a strange machine which drains all the blood from their bodies,which they then package and sell in wine bottles!