I've never purchased cigars at the Shilo but I would assume that they don't give you a separate check for them. They will let you bring your own if you are taking some along with you for your trip.
Also if you looking to visit a B&M, 82nd Ave Tobacco is not too far from the Airport (
http://www.82ave.com). They are typically open until 9:00pm. They have a small smoking lounge but I think you would have a better time smoking at the Shilo.