I'm with you on what's a fair price.

On the other hand, if the guy in front of me buys a notebook for $9, and when I get to the register the price is $14, I might very well say, "Forget it--I'm keeping my money," even if I might very well have paid that much if I hadn't just seen someone get it cheaper. I think that's human nature, and it's why companies tend not to vary prices that way, even though I'm sure they would, if they thought they could get away with it.

As far as not complaining, I think it matters what you're complaining about. I don't complain about prices being too high (I just don't buy things if they're not worth the price). I do, on the other hand, complain about inscrutable pricing schemes (such as the airlines), where you can't actually get a reliable price quote. I also complain about deceptive schemes, where you think you've got an agreed-upon price, only to find some extra costs get added on later.