I usually cure the garbage dog problem with a bit of raw hamburger and a bottle of expired syrup of ipicac mixed and placed on the garbage. Either the owner is freaked over the dog puking all over, thinking it is poisoned and keeps it home, or the dog remembers where he got bad meat and doesn't come back again. It causes no long term damage to the dog and is very effective, especially with those cute little house dogs that "never leave the yard."