Mac users don’t need them. Not sure about Insert, but Cmd+backspace, Cmd+up or left arrow, Cmd+down or right arrow give you delete/home/end respectively. Alt+up/down arrow gives you page up/down.
The fact that you don't need them doesn't mean everyone else doesn't use them, also, how do you know what every Mac user thinks? Also you know there are other OSs around don't you?
