Those Walking Horses on the video are trained for heavy shod showing. This is where they put a heavier and thicker shoe on the front feet and a lighter thinner shoe on the back feet. This makes them drop thier butt and keep thoes front legs in the air.
If done correctly the horse will not have any problems. Of course after a while it will wear and tear on the horse. Most of those horses only show a few years like that then are retired to light shod. Light shod is when they don't have the extra heavy shoes on the front.
I own two walkers and I show both light shod
To learn all that a horse could teach, was a
world of knowledge, but only a beginning. .. .
Look into a horses eye and you instantly know
if you can trust him.