I'm sure it came with a long explanation about it being a thorough explanation of the essence of man. The whole, sad "everything and nothing" routine.
This 1969 release is titles "Uberfordert" (EN: Overextended)
Featuring Wolfgang Domke. Transfixed at a table, a man drinks a lot of alcohol, eats a lot of beets and cream cakes in order to make himself vomit. During this hour long process he becomes disillusioned and talks about his concept of the future.