Yes I believe that duty free does sell smokes. Actually though smokes down there are cheaper everywhere you buy them. So even if you run out and go to the mart across the street they are less then 4 bucks. The problem for me though buying them down there is that they don't taste the same. After you loaded it doesn't matter, but I can definitely taste a difference I don't like. So I make sure to bring enough from home.
If you don't get the duty free ones on the way in, it's worth the extra trip to Walmart or at least a store located away from the hotel zone (sometimes I'll get the driver to stop at the first 7-11/Oxxo etc so I can buy a carton. You'll find you save about 20% if not more than buying near the hotel or even more if you buy in the hotel itself.
I didnt find Fire Ball in any store near the hotel zone. I was told there isnt going to be any to find. I know the airport didnt have it. Thats the first place I looked
Well then I would suggest looking if there is a duty free in your departing airport, and if it is open before you leave.
I think La Europa carries it if you stop there. It's a giant liquor store and the website seems to show them having it. WHISKY FIREBALL 750 ML
We always pack fireball in our checked bags. I just make sure to buy the plastic bottles. I bubble wrap the bottles and have never had a problem. We buy everything else we need/want at Duty Free in the US before flying into Mexico. Saves on weight and room in the bags. Not that I saw. I was there last week.