I think people have to obtain a waiver now for cash transactions larger than 10k usd. If I remember correctly, which is not always, but somewhere between often and occasionally, we are not allowed to keep ten thousand dollars or more on our person, or in our place of residence, for more than a particular amount amount of time, and you are supposed to obtain a waiver or something paper-work related, showing that this money is legitimately your money, and you are holding it for a purpose deemed acceptable.
im not sure i remember correctly. I know i have heard, you have to have a good reason for using cash, instead of a bank, for large transactions, but I'm fuzzy on details. Sounds like they are slowly herding us toward a cashless, bank dependent society, where anonymously purchading slim jims ad a pack of cigarettes will sound suspicious to the self subverting herds.