In a vaguely more serious vein, I think people actually do have some sort of negative reaction to non-human primates. Or at least are scared of admitting they might be intelligent. In doing some research for an essay about ape language experiments, I have run time and again into people who irregardless of evidence uniformly dimiss any possibility that apes could learn anything approximating language.

I think they decide humans are special because they have language, and so they are worried they won't be special anymore if apes can learn language. Just like when they used to say only humans made tools, or only humans had opposable thumbs, both of which are incorrect. Unfortunately, the evidence that apes can learn language from what I've read is more anecdotal than scientificly proven. Depending greatly on how you define language as well.