This question already has an answer here:
A short story written probably before 1980 and after 1960 but not sure. An alien race sometimes abused sexually (using orifices not meant for this purpose) by humans, they see the fact that humans drink a kind of "wine" made by torturing one member of some delicate race (this is a third race in the story) in front of its mate or something and collecting its tears as an indication of how degenerate humans are. Then these enslaved aliens are rescued by a warship from their home world. The aliens from their home world are larger (perhaps due to not being abused) and their planet is beautiful. But as a banquet celebrating their rescue, they are offered this same "wine."
EDIT: This is We Who Stole the Dream.