But there isn't really huge differences in the behaviours of humans and chimps. At our most primitive we're really similar. We have the same emotions and to non-primates we probably look very similar. I suppose we'll just need to agree to disagree.
The thing is we went passed primitive. If we are so similar why have chimps not built a city yet. They have had plenty of time. Same reason a cat does not chase gazelle like a lion, their different. Are their similarities, sure but were still different creatures.