One of my partners thinks it should be against the law for banks to buy this stuff. Regardless, there is no such law.
Nor do I think you will find any state law that says its use voids a document. However, I can virtually guarantee that if your bank ever has to go to court and wants to use a contract that carries white out, interliniations, lines drawn from here to there, initials, and any other sort of streamside modifications the other guy's lawyer will ridicule your bank and its personnel; e.g. "How would anyone in this court know who made these changes, whether they were made before or after the card was signed, and whether they were made with the knowledge and consent of all of the other parties to the contract?"
Banks that pull this kind of stuff deserve what they get.
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In this world you must be oh so smart or oh so pleasant. Well, for years I was smart. I recommend pleasant.