"Look at me when I scream at your soul! You loud sacks of filth and sour cream can hit me with your pain pinatas all day, but you'll never take the jellied fantasies of my wasted youth! My stomach is clear and my mind is full of bacon!"
Dogs are great judges of character. I suspect that the slims know this, moreover know that dogs do not esteem them very highly for just that reason, and that's why they hate dogs.