A father catches his young son sneaking a cigarette. To teach him a lesson, he says, "You want to be a smoker, huh? Well go ahead, smoke this whole pack!" He makes him smoke all of them, the boy gets horribly sick from it, and never wants to smoke again.

Essentially it's a metaphor for forcing someone to go all-in on something they wanted just a little taste of.

I think it refers to the old punishment for a kid caught smoking. You catch a kid smoking a cigarette and then sit there and force them to smoke one after another until the whole pack is done. They get really really sick.

So the analogy is take something you like and then force it on you 24x7x365 until you hate every moment of it.

I assume this is a reference to catching a child smoking a cigarette, and to punish them, and put them off doing it again, the parent forces them to smoke the whole pack of cigarettes one after another.

This (in theory) makes them feel sick and develop an aversion to the cigarettes.