Chocolate is poisonous for dogs
I cringed when they put down the dish of chocolates to try to get Richie to come out because chocolate is poisonous for dogs and in large enough quantities, will actually kill them. Their doing this also implies that they were in the habit of feeding him chocolate.
So, a note to the wise-if you lose your dog under the floor, try a piece of meat for bait instead, maybe in a livetrap. And never give chocolate to your canine best friend.