Throwing out old shoes more than 30cm

I live in an area with the very aggressive old ladies that patrol the garbage. They are super strict, like anything you do wrong the whole garbage bag comes back on your porch with a passive aggressive note. (they open the garbage bags and go through them to find out whose garbage bag it is.)

I'm a tall white guy and my shoes are 31cm. They keep talking about everything in the garbage must me 30cm or less.
Any suggestions on throwing out the old shoes? How hard it is to either cut them in half, or just cut 1.5cm off of the front or back?
Or maybe, I should raw dog it and just put the shoes in there, since they wouldn't dream shoes would be that big.

I googled all over for cutting shoes and don't see any answers.