@ocrdu:

One could even argue that those who don't complain don't care enough.

Oh, one could argue that, but first I would have to know the real meaning of the word complain. To me the word complain has a bit of a bad vibe. Complaining is different than giving (negative) feedback. Or being sarcastic. Or passive-aggressive.
"Could you pass the potatoes!"
"Why are there no potatoes this side of the table."
"As always the potatoes were in front of someone else, not me."
"Pass the freaking potatoes!"
"Excellent potatoes, next time could I get the potato bowl first because last time I got nothing."
Different tones.

So if complaining is more like nagging or bitching, then I would say that the ones who don't complain are wise and care enough so that they are not irritatingly whining about everything to everyone.

On the other hand if complaining is similar to giving negative feedback, then it may be that if someone never complains, that person doesn't care enough to make things great again.