You know what I really love? I really love when I tell a guest something at work, and they get all pissed off at me and act like I'm stupid. And then ask to see a manager, with this smug look on their face like they've really just done me a good one, or something. So I do, and my manager comes over, the guest explains what's going on, I say nothing, and my manager tells them the exact same thing I did, because hey! I'm following store policy! Imagine that!
And then they get all huffy and stalk away, and it's really just brilliant. Especially when said manager turns to me after they're gone and says "Well she was just an idiot, wasn't she?"