DO NOT!!!!! Give a harsh correction with ANYTHING!!! That will actually encourage him not to even give a warning. You need to go back to NILIF on a VERY LARGE scale. He gets nothing without earning it first. No longer allowed on the furniture. Thats a priviledge, not a right and his growling and behaving like a butthead has led to that being revoked. You need to remind him that you control the resources, not him. As far as toys and treats, you should probably start teaching him how to play the trading game. If you want what he has like a bone, you need to trade him something of equal or higher value. and continue practicing this throughout his life.
As far the food aggression, that can be handled in a number of ways. First off, he has to work pretty hard for that bowl of food. He gets nothing without following a few commands politely and then sitting and waiting until he is released to eat. if he moves even a little bit towards that bowl before he is released, you can either remove the bowl from him and ask him for a sit/wait again or you can remove him from the room. This means he is on a leash at meal times so you can easy remove him by just taking him out by the leash. Once he is polite and remembers his manners again, he gets to try the sit/wait again. Another method you can try, and i very much prefer this one, is while he's eating, add things around him of high value like chicken, hamburger, turkey. Though with feeding a RAW diet, it makes this method tricky because you can get much more high value than what he's already getting. With this method, they soon learn that when you're near them while they're eating, good things happen.
Question: did the growling start before or after you started feeding a RAW diet?
Shasta GSD 5/5/10 CGC, ITD, TC
"Dax" Thor z vom Weberhaus BCAT CAX2 CGCA ETD HCT NCO-1 PKD-T RATI RATN RA TC TKA 3/18/2013
"Hades" Guilty vom Blutfeuer 10/26/2018
Zena GSD 6/1/03-2/16/2016
Riley GSD/BC 1/10/05-2/1/2013