I hate petty school uniform rules too, but have no choice because all of the school in our area have pretty much the same rules.
As a parent on a low income, with no uniform grants in our area available, I find it expensive and difficult.
A pair of slip on shoes from Primarni are £3. A pair of lace up or buckled shoes with a heel size of within 1-2", not so cheap.
Skirts. Don't even get me started on skirts. The schools can have all the rules they like, but if the shops don't sell below knee length, pleated skirts, what am I supposed to do? In the end we bought a few sizes too big and took in the waist, it worked out cheaper than paying for skirts from the uniform shop.
It doesn't stop bullying, it never has done. Even back in my day if you didn't have the right shoes, coat and bag you were bullied and children in ties look stupid. These are children, not miniature adults.