People are idiots...but just so you worry less, not all dogs are allergic to chocolate. And they're actually allergic to cocoa so most milk chocolate won't bother dogs. It would also take quite a bit of cocoa to hurt a gsd.
I know this because we have a westie in the family that loves chocolate...he once got into a whole bag of hershey kisses and ate the whole thing...took the aluminum wrappers off and everything!!! They called the vet, and he said not to worry...those have such small amounts of cocoa that they aren't dangerous. The only downside was the dog was wired for the next few hours.
CD RE TC HIC 7/10