It's just the way if the world these days. Unless things are going 100% in their favour, some people just cannot be happy.
I said in another thread, just look at Abu Dhabi's fanbase. Footballing paupers suddenly gifted unlimited resources to purchase off the peg 'success' yet they are some of the most miserable, whinging, whining, moaning gobshites you'd ever have the misfortune to meet.
Too many people forget football (and life) is more like a rollercoaster ride than a straight rocket ride to the stars. They want the highs, but refuse to tolerate and accept the lows that inevitably come along with the ride. The dips are then endlessly moaned about, despite being normal and part and parcel of the overall experience.
I agree with Howard too. The whole social media circus, added to the ridiculously sensationalist media, fuel this nonsense greatly.
It seems much of the western world is full of entitled, spoiled people who don't know how to enjoy anything anymore. They want to cream off the best bits and reject everything else, forgetting that life and football don't work like that.
I've always said that your misery resides in the gap between your expectations and your reality. In a world where people's expectations are often wildly unrealistic, they are always going to be unhappy with their reality. That leads to frustration, and that frustration leads to negative expression. You end up in a situation where some people want it all, and they want to acquire it with ease. When that doesn't materialise, the moaning begins.
It's the product of a messed up world.
It pisses me off too, but all we can do is let them wallow in their own misery while we get on with enjoying and living the full experience.
Edit:
I just want to add that I think there is a big difference between those genuinely discussing issues with the club/team as they arise, and those who just endlessly moan simply because things aren't going their/our way.