Fanboys are by definition, fanatics. That's where the word "fan" comes from. A fanatic is someone who is so deeply committed to the person, group, team, object etc. that he or she likes that they cannot be convinced that any of the competition for said object of fandom is better or even just as good. I can't understand why fans in gaming are looked at with such scorn when there are fans in other hobbies who are just as rabbid if not more so.
Take football for example. Would you say a die-hard, life long (enter sports team name here) fan is (enter insult here)? Have you ever gone to a sporting event and tried cheering for both teams at the same time? I have. I've gone to high school football games where I knew players on both teams well. I cheered and shouted encouragement to both teams. People around me looked at me like I was insane. They cheered for "their" team and hurled insults and taunts at the other team.
It's the same thing for some people in video games. They have "their" team, be it a certain console, game series, developer etc. who they hold up as the best and consider all the others garbage. People who say that all the consoles/developers/game series etc have their good and bad points and that none is totally better than the rest are not fans. They are gaming enthusiasts to be sure (in that they enjoy playing games) but they are involved in the gaming hobby at a different level or different perspective from the fans or "fanboys" as they are called.
In otherwords, "to each their own". If you don't want to be a fan of one certain console or game series, that's just fine. However, that opinion doesn't give you licence to ridicule those who are fans of something. I bet there is something in your life that you really like better than any of it's competition whether that might be a certain beer, car, sports team, country, actor or actress etc. You can't like everything equally well, that's just not human nature.
