Some do, but I cook quite a few briskets so I keep the trimmings, weigh the fat/meat and grind it myself. I just use a Kitchen Aid mixer/grinder which works fine for trimmings, but you would burn it up on a whole brisket. A really good combo is a 50/50 mix of ground 80/20 beef and ground pork. You have to babysit them so they're not under cooked, but the results are pretty amazing.
Mike
