It allows those that need it to maximise their ability to look down on someone.
Note that "tattooed, idiot, tourist" contains three adjectives used to denote inferiority to the user. Tattooed: tattoos are bad, the user doesn't have tattoos so is better. Idiot: being an idiot is bad, the views himself as not being an idiot, so is better. Tourist: being a tourist is bad because the user has a long-term visa and knows Thailand better, so is better.