I know this is an extremely broad question, so let me suggest a framework. Legally, a "meeting of the minds" is necessary before a contract is enforceable. It is unfair to expect one party to perform a condition or covenant if they didn't know about it. In some businesses, like car sales, unwritten "rules" are part of the game.What promises by both the buyer and the seller would you like to see regarding honesty and fair dealing? Why? How should consumer contracts and ethics change our existing business climate? In general, "Is what is 'legal' the same as 'ethical?'" Your thoughts may be better if applied to your past experience with an actual example of when someone went beyond the legal limitations of a contract, but won faithful customers as a result.