When I was thinking about this, an analogy came to my mind.  Nice guys are like fresh organic juice.  Bad boys are like a carbonated drink like coke.  If people are given the choice between organic juice and coke, most people would prefer coke because it's stimulating the mind.  People are more likely to eat addictive foods than normal healthy organic foods. Even if they are fully aware that the addictive food is toxic to the body.  One reason being that addictive foods are stimulatory and activate dopamine in the brain. They work on stimulation receptors.  However healthy foods do not cause such a response or reaction.  They don't alter brain chemicals.  Bad boys are attractive to the brain because they stimulate the responses for romance and attraction.  Nice guys are healthy and not toxic but they are boring like the organic juice. Since they don't stimulate the brain, they don't attract and thus the brain doesn't accept them even if they are healthy.  But a more conscious person will bypass the brain chemistry and think using a big picture of health and happiness  Good luck