Contracts in the US also require consideration (IIRC from my intro biz law class). IANAL, but I think that the consideration is allowing you to use the IP (in exchange for your compliance with the license).
> Promissory estoppel/detrimental reliance: A contract without consideration is enforceable if the nonperformance of the promisor will cause injustice. Elements of promissory estoppel are (i) the promise has reasonable, foreseeable, and detrimental reliance on the promisor, and (ii) the enforcement of the promise is necessary to avoid injustice.
In this case, you are nearly correct that the performance to honor the terms of the contract is essential, but technically not a consideration. (The IP code is consideration though.)
I don't think accepting a contract can qualify as consideration for that contract, as otherwise there would never be a need for consideration in any contract.