What is it with Dogs Anyway?

Coming in through the basement this morning after Lola's trip outside, I am hitting the button for the elevator and look over and notice her snuffling with her nose and mouth on top of something on the floor. I call her away and see that it was a water bug, on its back, still alive, legs kicking in the air. I just stare at it in horror, practically gagging and shuddering. The dog had her nose and mouth on that thing! I try reasoning with her, "Now, why would you want to touch that gross thing?" (Lola, just looks at me). I'm still shuddering over it. Why is it that something so repulsive to humans, always seems so appealing to a dog??? Dogs are weird. Well, at least she didn't eat it (GAG).