"You don't need a guitar to make music, because people once made music by banging two sticks together". I mean, the GP even specifically mentioned pie tins, cake containers, cupcake trays, and you retort with "baking is nothing but bread"? "You don't need stuff, because a simplified subset of what you want to do can be done without stuff"? Hell, you don't even need a hammer to drive a nail, but it's a lot more efficient if you have one.

It's doubly weird that you invoke how people ran 100k years ago, and then say "all you need are shoes". Nope - it's "no footwear". It's perfectly doable - I had an anarchist friend who spent several years without wearing shoes (excluding when he had to - boots for protection when motorcycle riding). You should ditch the shoes in your example, for both running and walking, as shoes are just as unnecessary to human locomotion as $1k of kitchenware is to baking. There's even a subgenre of running that is specifically about no shoes; I'm not aware of a subgenre of baking that is specifically about making cakes with no mixer.