This reminds me of my meaties. I feed my chickens bread while all of the smarter birds stand there & fill hide those dumb meaties grab a small piece & run all over the yard. As soon as one takes off running the other meaties start chasing it even if they have a piece in there mouth.
At least my meaties don't have leg problems but there running all that extra protein off I'm giving them. They don't grow very fast when they take a bite & go on a 15 min run.