What dogs will do to get a treat!

It's simply learned to beg for treats. Isn't this why dogs are trained with dog biscuits and such? They eventually learn that doing something will earn them a reward for it. Repeating this over and over becomes a habit and it will eventually keep doing it because it's getting something. Also, while dogs are more favored because of not only the intelligence, the loyalty and it's many uses, pigs are actually more intelligent than cats and dogs (http://www.nbcnews.com/id/24628983/ns/te...0bZ6-TQiaw)