These folks feed their dogs in a natural fashion. Dogs are really just funny looking wolves and they feed them whole meaty things the way wolves were meant to eat. (corn and wheat in dog food causes a lot of problems for many doggies... they were never meant to eat grain)
Anyhow, many feed whole critters to their pets. This includes whole fish. A gar would be just too hard for a dog to chew through. I doubt the scales would digest and gar roe is supposedly toxic. (I don't know if it's toxic to dogs, but I'd hate to find out the hard way)
Speaking of gar, we already ate all of our fillets. Have to get more. It's rough but somebody's got to do it.