Perhaps the answer to the hate for the human ape link lies within the fact that primates, like chimpanzees, display cannibalistic behavior. And being a cannibal is not very humanistic. Hannibal ring a bell. Though the reasons why chimps may show these behaviors and humans may exhibit similar things are usually drastically different. Perhaps survival as a monkey is more difficult than survival as a human where much of the world is getting fatter as a result of fast food and other nasty things like the variety of meat at the grocery store. Humans don't even need that much meat. It gets eaten any way.
There are three general reasons why people get offended by being compared to apes. First, apes throw poop. Second, religion is extremely influential in our culture. And thirdly apes are to dumb to display cultural difference. Which the first and the last on this list can be easily abolished the center is where most the explanation can come from.
Poop throwing. If you were raised on a farm that had cows you may have participated in what is called a cow pie throwing contest. Shortly it is basically the country style of dodge ball but instead of fancy red balls, brown cow dung hard on the outside and squishy in the middle are used to throw at your country counter parts. And personally my mom and her sisters played this game often as children. There was some intelligence, accuracy, and deviance required to play. Not only is this also a girls game, it is one played by humans. First you need to be able to pick up the best cow pies, second you need to aim at your siblings, and thirdly you need not be ashamed of showering off the cow dung that splattered your face shortly after playing the game.
Religion is to difficult to dive into at the moment. So let's skip to cultural difference. In America, we eat at the table. Oh wait that was like 60 years ago. In America we eat on the go and most likely without family nearby. And plus we eat disgusting salt and fatty items. In some parts of India, people eat on the ground and have a personal relationship with their food.
Apes have culture. Kinji Imanishi suggests that “Japanese macaque develop behavioral differences as a result of social, rather than genetic, variation.” Live Science by Corey Binns Simply put, monkey see monkey do. If different social trends happen in different parts of the world in apes it should be no surprise that parts of the world value their food more than others. Humans pick up what they see.
So the explanation can only be left to culture. Many Christian based cultures teach that monkeys have no relationship to humans and how humans behave. However intelligence is passed on similarly to monkey like behaviors. Human hear human preach. And this thing is passed on from generation to generation just like monkeys and poo flinging.