This is a gem...
Using your line of reasoning, you would see nothing wrong with an individual playing Russian roulette if it gave the individual pleasure. Beyond the questionable mental health issue of this practice, if these individuals were playing with some elses head next to their own would you still see no problem?
A great analogy for the social psychosis generated by Pavlovian behavioral conditioning in popular culture (although argument from analogy is informal fallacy, but often applied logically for those whom logic fails).