> Promises agreed to in contracts that restrict your ability to modify games are enforceable.
Could you provide some case law for that statement. Contract law is a complex area, and Meeting of the minds is critical aspect in order for it to be enforceable.
As a consumer, I have bought my fair share of games, and not a single time was I informed about a contract. When talking about consent, EULA agreement is as far away from reality as you can make. People have signed away their eternal soul (http://boingboing.net/2010/04/16/video-game-shoppers.html), while a study showed that average users spend less than 8 seconds to read agreements (https://dl.acm.org/citation.cfm?doid=1753326.1753689). A similar study done earlier in 2001 looked at privacy policy documents and found that only 3% of consumer read privacy policies, and once they read it, they were less sure about what it meant than those who didn't.
But the legal system is complex and not always about common sense, so lets look what the court has said in specific cases. Looking at shrinkwrap licenses, about 4 know cases has ruled against enforceability and 3 has ruled for it (http://euro.ecom.cmu.edu/program/law/08-732/Transactions/Shr...). The primary argument seems to be about when the contract is formed, as in the store when money and product change hand, or at some later time. One camp states its in the store, and the other when the customer has performed a arbitrary number of steps (purchase, picking something up, turning a thing on, ...). The first camp is focused on the consumers ability to consent to a contract they haven't seen or understood, and the second camp is focused on current industry practices. The conclusion seems to be a distinct lack of supremer court cases to decide which camp is right.
