It was in their letterbox, as I read it. We are not told if it was placed there by the postperson or a store representative. Are they saying the dog knocks himself out just because it is an advertisement? Or might he do this for any brightly colored Christmas card? Perhaps they set him up for failure when they named him
Muffin!; he has to pull stunts like this to prove his machismo?
Be that as it may, you are so right -- s*#@ happens.
Yep. Poor dog.