You'd be surprised. At least where Ultron is concerned. Anything Stark does is an offense. He's really playing up the rebellious teenager angle, it seems. Fortunately, without flight, Ultron seems to be having a bit more difficulty navigating the shrubbery.

Fortunately for Stark, anyway. The AI on the other hand is apparently only further angered by the obstacles, going so far as to tear a branch off a sapling in order to storm past it.

"Oh, I don't know--" He flings the branch from his hand, where it impacts an empty cage and shatters into splinters. "--Perhaps it was your attitude, or maybe the way you style your hair, or, hm. Let's see."

He picks up a rock, at a loss for any other convenient weapon.

"Or was it when you took everything from me?"

Ptchoo, goes the stone.