Well, he doess not have dactyls(smashers), so he would not exactly be able to whack the stick in defense. they are also noted as being outgoing, so he probably isn't scared of the stick anyways. if you have ever given him food from the stick, he probably just though that it was dinner time.
Funny: I just put the stick into my G. Ternatensis' tank. Whenever i do, she gets excited (I have only had her for 4 days, and she already knows that stick=food. In this case, I usually let a snail climb onto it and offer her the tasty escargot). Anyways, she didn't strike it, she even let me push it right against her, taping(lightly) against one of her dactyls. No problem, she must not see it as a threat at all, or me, for that matter.
On the other hand, my friend Scott just leaned in while we were watching her smash a snail. She ignores me, or looks up to watch me from time to time whenever se is eating and i am watching. Scott said 'What's she doing?'.
I looked and there she was, in full threat display,facing him down through the tank. He laughed and that seemed to make her more agitated (perhaps the sound was intolerable, I know that I think his laugh is annoying...). She rose up higher, climbing between 2 rocks and opening her arms wider and flaring her antennal scales . He backed down, because he knows what's good for him (I was also saying, go ahead, put your hand in there,man...she wants a hug).