Because, to the hyenas, it would be much easier to kill a zebra and eat it than start a stampede. One meal doesn't seem very convincing. True, the hyenas were dumb, but it doesn't take much brainpower to ask "what's in it for me?" Even domestic cats can do that.

[quote="LeonaInez"]Yes but things were only in such bad shape because of the hyenas eating all the food. If they weren't around, then the land would have been in much better shape and the lionesses probably wouldn't have been mad at him.[/quote]
Scar: "I'm the king, I can do whatever I want!"
I doubt the lionesses would tolerate his attitude, even if the Pridelands didn't become a desolate toilet bowl.