Victor, you have asked a very good question and have a very good observation.
I will speak for myself. As a member of QQ since 2014, QQ has opened me to a world of music that I could have never imagined. I am listening on a regular basis to artists that I would have never known about. Here in the San Francisco area we do not have good radio stations, we don't have MTV anymore, as it used to be, so if not for QQ, my musical tastes would be very narrow and not open minded.
Of course and everyone will agree, we purchase something that many say is great, and I find I don't like what others like. Just like I can have a favorite band but don't like one of their albums, etc. I am a 50/50 listener of stereo and surround. It depends on my mood, sometimes surround is to engaging for me and I prefer stereo, but when I can calm down, surround is where it is at.
Your observation of others always seeming to complain, I agree with you. My theory is that when others complain on QQ, not all the time of course, that they like to come across as "I am a very good audiophile of the highest standard and I can hear everything that is wrong all the time". I, of course would never call anyone out on that as that would not be nice, and for God's sake, it is just the internet, and we get what we get. All that said, I have made some wonderful friends on QQ and would highly recommend QQ to anyone who has an interest in music.