Cheetah is just a bot, it doesn't know the context of your post. So long as enough of it is copied from somewhere else cheetah will stop in and comment on it.

Correct, you are not being called a cheater or flagged by cheetah. In order to avoid cheetah you would ideally be writing completely original content, but just because cheetah does comment on your post it doesn't mean that you have done anything wrong.