Possibly, but gaming is how I spend significant amount of my free time. During this time, I'd rather play quality games, so it's interesting to clarify which factors can make a game better or worse. That would allow me to choose better games to play, as well as recommending better games to interested people. Hobby or not, if you pour thousands of hours over the years into something, it's not surprising it starts being given more importance.
Discussion of this nature might reach the attention of people involved with the game industry. That way, the player opinions can influence, even if slightly, the direction that the gaming medium goes. Also, don't forget that, for the people involved with the game industry, discussions of this nature are undeniably serious, since they involve considerable amounts of very real money, their livelihoods and investments.
Besides, I do have an interest in game design myself, just as people may be interested in literature, paintings, music and the most diverse subjects. Are we not allowed to? What is the problem in discussing seriously about something that you like? Why would not taking it seriously be better in any way?