Why do carts only have swivel casters in the front in some countries, while in other countries, it’s all fours?

Question

I can’t help but notice that the back wheels of shopping carts are fixed in the States and Canada because I recall such being not so much the case in other countries like Japan and South Korea where the shopping carts there are all swivel casters (yes, that’s including the back wheels!) with some additional grooves on one of the back wheels to keep it from falling down when customers go up these moving rampways (they’re kinda designed like escalators but instead of individual staircases they’re flat tiles forming a ramp to allow the shopping carts to also go up the floors with the customers).

In: Engineering

Answer 1

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