If something is specified in the contract, I find it difficult to see how this can be called "trickery", it is a magician telling you in advance that he may hide the coin up his sleeve.
You seem to think that each party should simply expect the other party to try to get as much from them as possible, through whatever misrepresentations and legal strategems they can get away with. Maybe this is normal in the areas where you work - I guess Jacques and I both come from backgrounds where this would be abnormal, and in fact disgusting behavior.
In my experience breaches on either side tend to get netted off fairly amicably. I might swap you a change request that you want for signing off a performance deviation I can't avoid, that kind of thing.
However the contract still serves a purpose - it provides the ground rules for that kind of trade. It does sometimes happen in bad faith (usually when the contract has a long and sticky history already) but most of the time it's just a more formalized version of goodwill. And that formality is necessary when you are talking about millions of dollars per change.
I do not "expect the other party to try to get as much from them as possible", I just expect that should one party fulfill the obligations of the contract, that the other party fulfills theirs.
The point of having a contract is that I can do business without invoking any kind of ethics or morality based on a background I presume to share with another party, or my own personal definition of "misrepresentation".
Or at least, I can advise the other party of my definitions and expectations in advance of them entering into the contract of their own free will.
Whole mafia of lawyers earns big bucks thanks to making these contracts even more convulted.
Outsmarting somebody by clever legalese isn't moral in my book.