I think that has to do with moreso the logical side of our brains scott. People can be cruel. We maximize our own pleasure, and sometimes people come to the conclusion that the way to do that is to hurt others. Selfishness, greediness. Sure it helps yourself but it doesn't help your social image. Alot of people find dogs and other less intelligent creatures to be more trustworthy because of that. Hence the common association with Dogs and Loyalty.