I think the pictures speak for themselves.
In those shoes, the 4" padded ones, my mare had marbles and at another point a golfballs with screws in them. She had open wounds on the backs of her hooves, and her hind end is majorly screwed up muscularly. It's going to take me a while to get her back into shape. She had kerosene put on her legs. It's pretty horrific what happens to them. The barn I bought her from had SIX USDA violations in ONE YEAR. They were still operating and showing.
Thankfully, in the 3 weeks I've had her, she's had a complete personality change. I love her so much, all 17.2hh of her!