I reckon there must be half a dozen cans of shoe polish and suede protector in this house, and they would all have been side-purchases , along with shoes or boots. It's like, every time you buy shoes from a non-discount shop (or maybe even those ones too), the sales assistant says something along the lines of "and would you like some shoe polish/leather conditioner/suede protector with that?". And I always fall for it, even if it's 10 bucks a can and ends up filling a forgotten corner of an out-of-reach shelf in the spare room.
I wonder how much of that stuff would get sold if it wasn't always pushed as the only thing to keep your precious shoes from looking less-than brand new.
Personally, it would be healthier on my wallet if they just offered a small bag of fries.