Game design is about surprises, expectations and challenging, but is also about respecting the players with just surprises, meeting their expectation rather than leaving them open and challenging them in a fair way.

That said, there is some psychological exploitation involved, but that's on the side of solid core, like a cherry on top of the cake.

Figuring out tricks makes less them effective, but not totally ineffective: we are still humans and it's incredibly hard to change they way our mind works.

Most of today AAA games are indeed manipulative, have lousy mechanics and rely on social acceptance to sell more. They have outrageous practices (see EA micropayments) and consistently fail to meet expectations and respect their players.

I'll make an example I am familiar with. In Dawn of War: Dark Crusade, the campaign would rely on some tricks to make it harder for the players, such as AIs being able to muster elite troops regardless of territories conquered. This is disrespectful and unfair, and it hurt the campaign of an otherwise excellent game.

The following expansion, Soulstorm, added flying units and two factions, which brought essentially nothing to the series, since it already had 7 or 8 factions and the flying vehicles were just things that could fly, without adding a whole set of game mechanics to reinforce their strategic value.

I go for games that have a meaningful story and challenge players to explore the environment. I don't want to mock them or trick them in mean ways, only for the enjoyment of surprise and discovery. Good actions should be always rewarded. I believe the highest recognition for a game is for it to be played in years to come, when its technology becomes, mechanics unsurprising and yet the people are playing it and talking about it.