One of my dogs discovered a (wrapped) box of chocolates under the Christmas tree last year, opened them, ate 5 and had a fit/seizure. Eating chocolate can, as with humans, have a detrimental effect on teeth, in addition to the chemical effects of the chocolate on the brain/body. I think it's difficult/unwise to generalise and each animal should be treated as an "individual" before condemning/condoning anything relating to that animal (whether 2 legged or 4 legged).