Almost every furniture or non-living object, is used till it's not useful anymore and thrown away. (Their size depends on the size of your feet. Sometimes, they are made of leather, sometimes cloth, and they have a sole at the bottom, and a shoe lace or something else to prevent it from getting lose from your feet.) When you buy shoes from a shop, you would probably like them because thet are new, you'd clean it every day. Then slowly it gets old, it's not so pretty anymore, the glow vanishes and it has scratches everywhere. You don't wear it anymore, and finally, you throw it away. .
If the shoes were a human, I would think it as a mother, and the feet the child. Like this: The mother cares for the child, she loves her and the child loves her mother, because she is so beautiful. But the mother gets old, wrinkles appear in her face, and the skin isn't as lovely as before. And then the child starts to hate her mother for being so ugly, and 'throws' her mother away.
Of course the shoes aren't human, since they have no soul and feelings. But you would find it a little sad (or preposterous). You wear shoes all the time, in school, outside, in the supermarket, at the hospital, in shops, on streets etc. They protect you from injuries, and too low or too high temperature. Imagine you would step on a broken piece of glass without shoes, or stand in snow with bare feet. You could not even stand still for a minute, much less walk or run.
Now shoes are mostly thrown away before they are useless. Especially children's shoes because they are growing. In the past, there were more poor people, who couldn't afford new shoes, and the shoes were not so good.