Earlier quoted context omitted.
It's not about the difficulty of raising prices, it's about the impact to the bottom line profit to shareholders when a few cents is extrapolated over a billion transactions.
The percent impact would be negligible, I expect lower than daily fluctuation. Anyway, the law isn't just designed to protect shareholders, it's designed to protect everyone. If someone can make money by fraud, that money is not justification to allow fraud. The US economy relies on dependable contacts.
Which law? "The Law" as an ideal, is impartial. That's irrelevant. In practice, applied law (and the cousin enforced law) leads to biased results, favoring the wealthy and the status quo while remaining "impartial".