If chocolate is so bad for dogs, why do they love it so much?

Animals in the wild tend to avoid the things that will harm them. Of course, wild dogs probably never got to taste chocolate -- the cacao nut is a pretty tough nut, and most dogs couldn't crack it on their own. They'd have had to depend upon their Mayan masters. (Did the Mayans have pet dogs?) But I'm thinking, where dogs are concerned chocolate must be an acquired taste.

Personally, I always thought it was the endorphins. Chocolate makes me feel good. So it most likely makes dogs feel good, too. But the first time Bao encountered chocolate, how did he know it would make him feel good? Why did he want it, even before he knew what it was?

(I must confess, these are the sorts of questions that occupy my mind when I wake up at 3 AM and can't get back to sleep)

Anyhow, it might not be the endorphins. Chocolate is sweet. And dogs (and humans) are genetically predisposed to be attracted to sweetness, which signals carbohydrate energy -- useful if you're running away from sabre tooth tigers and other such predators.

At this point in my meditations, I ate a Hershey Bar and prompltly dozed off. There's a lesson here, somewhere.