Dean's okay with it, honestly. Eye-rolling is better than several of the alternatives and, sometimes, it's even as good as a reward. He's also not likely to put up much of a fight with anything Felix wants to do, now or back on board; he'll be there, whatever form Felix's coping methods take. He's willing to be one of them. More than.

The hunter doesn't like the cigarette, he never does, but there's so much else to be concerned about that he never says anything; besides, he's not Felix's mom or big brother. He has plenty to fight about without that, and Felix never shoves it in his face, so he just picks up another chicken thing and smirks at the reaction. The feeling in his stomach still doesn't quite match what the surface of him is doing, but it warms a little bit at being right, at the familiarity of it both in Felix and because he's seen it before.

"Please. With me driving, you don't even have to ask," he quips back, cocky, though this time deservedly so. He's already plotting it out in his head, and there's not even any resignation or disappointment there; it's not a place Dean would go on his own, but for all his complaining, it's not that he finds nothing about science interesting. He's just very limited in what it applies to. And anyway, he can theoretically do anything he wants once he gets back to where he came from and it's not headed down the tracks for an apocalypse anymore.

That's if he'd ever say no to Felix anyway. "You just finish up your lunch, and let me worry about getting us there in time."