"Oh, thanks for the offer, kid, but I don't drink during a job."
A lie, not even intending to be true, but that's not the case. Fractal just went on with it, just for fun. Probably he would leave the Stuffer Shack with some beer or wine (depending on his mood and the temperature) before starting to work, but after looking at the label of Sam's bottle, his drive to drink somehow almost disappeared.
Is this part of your idea? The bottle has something to do with a peace offer to some gang or will it be a improvised weapon of the new kid in the block trying to prove himself persona you'll impersonate?
Fractal was a little preoccupied with the safety of Sam. He seemed confident enough that it transpires that he could care for himself; but last data was that at the facility people got hired security and maybe some nasty drones. As he said before, better to be safe than sorry; at least, until the run really start and they dive deep into it.