The closer to humans they get, the more qualms we have with killing and eating them. Primates for example rarely are killed and eaten by Western cultures.
Dee: (picking out meat at the Chinese deli) OK, well, we'll take, um, that big brown mound and the curly stuff and then this thing that looks like a blanket.
Charlie: Try some of that.
Dee: Definitely.
Charlie: Oh, oh, oh! What about, uh, monkey? Monkeys are, like, nature's humans.
Dee: I doubt they have monkey, Charlie.
Charlie: People eat monkey, Dee. They ate it in Temple of Doom. You ever see that?
Chinese Butcher: Hey. We got monkey.
Dee: Oh! Well, will you look at that? Great. Uh, one monkey also then, please.