When the fire began to look under control, I accidentally overheard two fireman talking, on account of I was eavesdropping. Upon entering the burning building, they had found charred columns of inventory stacked to the ceiling. One could well argue that Smitty's inventory always looks like that, piled high with no apparent organizing principle. But --- to the ceiling? Thus the fire was provided with fuel enough to climb to the ceiling, and the second floor.
We hope there will be an arson investigation. There are obvious potential motives to burn Smitty's. Insurance, for example. Or developers lusting after the block Smitty occupies could have decided to hasten his departure from the neighborhood. There is also the "second wino on the grassy knoll" theory. A single hapless alcoholic breaks into the building in order to have a place to sleep unmolested, falls asleep while smoking, et voila. Personally, I discount the second wino theory. (And yes, conspiracy buffs, I am also convinced Oswald fired the shots.) Follow the money, and watch for the fire marshall’s report.