The purpose of the pads is to extend the functional toe. This delays breakover in the stride and causes the foot to come off the ground with increased energy, giving a longer and more dramatic flight. If you add weight (illegal now, but not so very long ago) you add even more energy to the flight.
In the flat/light shod world the same effect can be achieved by a long toe and low heel trim (that's called being "long and low"). They can't use a pad to artificially lengthen the toe, but they can aggressively trim to get the most they can get before the hoof material fractures. Here the horse can wear a shoe that can legally weigh up to 48 oz. The farrier can also shape the shoe to ****** breakover, all in an attempt to maximum energy at takeoff.
The search for maximum energy comes at a price. It is a very mechanically inefficient system. It requires a lot of equine energy. It is designed to make movement vertical vice horizontal. IMO it also grossly stresses the shoulder, back, hips, stifles, hocks, etc. Those stresses cause short and long term lameness.
The pads, bangles, balls, beads, etc. are the hallmarks of ignorance in training, IMO. But they are not the root of the evils that beset the Walker. The root is the quest for ever increasing "front end action." Until that goes away the problem will remain.
I can't tell if the foot, here, is "enhanced" or they've just got a farrier who can make it very long and low.