Why can't you wear white shoes?

You can, however it's considered unfashionable to wear them before Labor Day or after Memorial Day.  I don't know who came up with that, but many people follow that rule.

I always wear white shoes playing Badmington

I COULD BUT I Don't want them.

If you step on king kongs feet your shoes instantly turn black. No not black but a mud kind of way.

I just purchase white platform sneakers,  does that count?

Because I am not good at keeping shoes clean