Any dog trainer that has been practicing for over say... a week is familiar with this phone call. The dog constantly grabs everything from socks to steaks and darts away hoping for a chase. If the humans ignore the behavior the dog, largely undaunted, often will just make themselves comfortable playing with, chewing, or eating the item.
Some of the clients have read or been advised by another trainer to trade the item for a treat. Then the client proceeds to tell us this has done nothing more than trained the dog to keep grabbing the items to trade for a treat. Or the client's partner won't do it because they think it is rewarding the "stealing". And as often as not, report that their partner has tried smacking the dog. And since they are calling, we can safely assume that didn't change the stealing behavior too much.
So what to do? Ignoring, punishing, and trading for treats haven't gotten us where we need to be. The first question to ask is WHY haven't they worked?
Your dog isn't stealing. What your dog is doing is retrieving. Picking up items and bringing them somewhere. And humans have been selectively breeding dogs to retrieve for over 10,000 years. And way of life hardships and challenges over the last 10,000 years have been tremendous. We have bred them to retrieve through it all. Or we and they couldn't eat. You can't punish the retrieve out of a retriever (or any dog, but retrievers such as labs, goldens, poodles, and spaniels do it the most. And because doodles are often poodles mixed with labs and goldens as their popularity goes up, so does "stealing" behaviors.)
So why didn't ignoring work? Partly for the same reason punishing didn't work. We've worked too long and hard to get them to want to retrieve through any adversity. And as a result of selective breeding it is inherently rewarding for them to pick up items....And to chew them. And, if they get a game of chase out of it sometimes, that's even better. So ignore all you want but your dog will probably still retrieve.
What about trading for treats? That might not be a good long term way of life solution. But it actually IS a good start. It isn't as rewarding as a game of chase. And it doesn't encourage taking off with the item. It doesn't stress them like getting punished for a natural instinct. And it prevents a dog from developing resource guarding tendencies which often evolve when treasures are taken from a dog often enough for long enough.
The other benefit of trading for treats is that it sets us up well for our long term solution. We know we can't punish, ignore, or reward a dog's natural instincts out of them, but we can harness the instincts and make them work for us. It is actually very handy to have a dog that will pick up your dropped items and bring them to you. And rewarding any bringing is the first step. So you are well on your way! This training does take time and patience and usually professional guidance. But for now, start saying "bring" as your dog brings you the item to trade for a treat. Then start dropping things on purpose and saying "bring" and trading for a treat. Then start only rewarding the "brings" you ask for, and make sure there are plenty.
What else can I do?
The stim of a retrieve or anything in their mouth is something most dogs seek. They also seek the enrichment of games, running, social play and problem solving. So providing these other ways will cut down on them finding their own way (probably your shoes) to meet the need.
Some ideas that help are: Making sure your dog is getting significant time on a long line or off leash to run and explore
Teaching your dog to fetch and tug
Providing lots of very satisfyingly chewing/mouthing items the dog CAN have.