The fact that wine was so generously provided without much question is a significant signal to Knobbenkirk that things aren't so easily slipped past this woman. Perhaps there were beastly senses beneath that beastly skin? Knobby reassesses the situation and accepts the glass with a quenching swig.
"Oohh, that's nice," he comments. "Okay, well, you got a sharp nose there. The truth is, I was following you, because I wanted to see where all the goodies were. I figured if you were getting something to eat and drink, and you were getting it all by yourself, you probably got the inside scoop on the kitchen and larder; at least, moreso than those two fancy folk with the high noses and perfect faces.
"Anyway, so I was all set on checking things out, when you got way too efficient with the food-prep and next thing I know, you're heading back to the main area and asking where I was. I figured it wouldn't look good to suddenly pop out behind you, on account of how you had to hold all the munchies, so I stayed quiet and followed you again back into this place."
Knobby puts the bowl to his lips and swallows a helping of stew. "Where was I? Oh, right. Now, you might think that if I was so intent on checking out the kitchen, I could have just stayed in here while you were being a good servant. But I didn't, because that'd be rude!"
The gnome pauses, inwardly inspecting his bodily condition to see if he's been poisoned in any way, or at the very least if his stomach is halfway to contentment.
"So, yeah. That's pretty much why."