Let me play devil's advocate here.
I guarantee you without exception that any Big Lick owner/exhibitor that shows that way will tell you "WELL, it DOES happen, but MY trainer doesn't believe in it, so he/she doesn't do it" and totally believe it.
Why do they believe it?
Because they are not there the majority of the time horse is being trained, nor when horse is shod, and really and truly believe their Big Lick horse is moving that way because it has "been bred to do that."
They mostly have no idea what is being done, or buy the excuses the trainers give them.
IF they were honest, and really wanted to know? They would be refusing to show Big Licks. Plain and simple.
Same with any other discipline, IF the money leaves the barn, and the judges quit awarding ribbons and placings to horses that have been done this way? IT would STOP overnight.
As long as it is rewarded it will NEVER stop.
And frankly, I've never met a Big Lick owner/exhibitor that had much sense, nor were they anyone that I considered concerned about their animals in any way, shape or form. No matter their social strata either, rich or poor, all of them are tarred with the same brush.
Horses make me a better person.