Strick,
I've not heard of weights wearing out the pockets of a weight integrated BC. I suppose it's possible that poor workmanship or a material defect could eventually result in a pocket failure. However, I suspect that would be rare.
However, I HAVE heard of weights coming out of pockets. At depth, as I'm sure you know, such an event could lead to a potentially dangerous uncontrolled ascent.
In several instances with which I'm directly familiar, it was a failure of the fastening device holding the weights in vest, not the pockets being worn out. In one, the velcro fastener closing the weight pocket was fouled with sand and debris preventing many of the hooks and loops from engaging. In another, the fastener, a buckle device, came undone.
Actually, I have more concern that I am going to forget to put the weights in the pockets rather than them falling out!
Warren