What's Blank looking for in his old high school locker? It looks like some splinters, but it's not too clear what it was.
Weed, dude. It was weed.
What the hell is the whole "POPCORN!" thing about? Why does he keep saying that?
That's the sound of two rapidly-fired semi-automatic pistols.
He's also insane.
"Popcorn" refers to expendable mooks, cause they're cheap and get munched quickly. Grocer is saying that Martin isn't special, just popcorn...which kind of goes against his obsession with bringing Marty on board, but again...he's not quite all there.