I think its mostly a manufacturing thing, the way they prepare the unfinished cans and how they crimp the tops onto them at the canning facility. (I took a tour of an aluminum can production facility many years ago) I thought that smooth sided cans pretty much went out when they got rid of the steel cans that had a seam down the side. (Although I've heard there was an experiment many years ago with steel cans that were almost indistiguishable from modern aluminum ones without looking for the steel logo on it, or using a magnet. Now that aluminum is getting expensive, I wonder if that might happen again?)
Give me some cane sugar Pepsi in a glass bottle!!