What weird habit this is. I believe its something that is lacking in their diet.
But others say it is a nervous thing.I have never had it with my dogs and they have a varied diet with fresh meat brown rice and veggies, sometimes I grate raw carrot to mix in.
They also love garlic. When they go poo they cant wait to leave it fast enough. This is just my opinion.
I think it common for dogs to eat poo my vet said it happens allot he sometimes the dog food they eat is the culprit if in not higher quality it smells same going in and out or learned behavior form mom or watching owner pick it up or to clean the area or boredom or for attention or over or under feed.He gave me a helpful hint feed all your dog pineapple with their meals not very much a little will do it makes the poo smell and taste bad and they will stop eating poo it worked when i tried it
We have a border collie/lab mix too, and she doesn't like dog poo, only cats. We have to keep a gate in the doorway of the litter box room. Our sheltie used to dig in the snow for dog poo, we called them poopsicles. Disgusting, other than watching them (which you can't always do) I don't know of anything that will stop it. Does yours constantly look up in the sky and chase the birds. Ours does, and doesn't watch where shes going, and smashes into trees.