Relying on Nat's "discount", while watching a failed version of the same tactic going on right in front of you, sounds hilariously dumb/naive.

Refuge in Audacity.
It ALWAYS works.
For certain definitions of "always", with qualifiers.

Not exactly the same tactic. High-level diplomacy or thievery is more likely to work than low-level thuggery.

Luke: "Who should we be helping?"
GM: "plot plot plot plot"
party: "Nah, let's just ignore it"

Well, to be honest, I don't really understand who the GM is expecting them to help either.
Or what to do at all.
Maybe they're supposed to help the chef to impress the head-chef, but other than that?

Personally, if I was the GM doing this I'd be doing so as a way of explaining why it is that our good ol' Waiter #3 is so awesome, he's in the company of retired adventurers and a one-legged legend! Nobody is supposed to help anyone else, at least, not yet.