Two reasons for you, that guy: first one is that there are always people who care, in every business. There are people in the movie business who say for example superman is good and others say batman is good and so on and this is true for every part of life I think. but it is important to see that we are the minority. most people do not care about who built their console, but some do and they are arguing.
the second point is that it does matter if your system wins or not, which is the difference to the movie business or the car business or whatever. I for example buy nintendo consoles because I like the nintendo games and I don't want to buy more than one console per generation. This means that I miss a lot of good games, but if my system wins, I will get a lot more of those good games.
