Exactly and further, the law was enacted to thwart the "laundering" of illegally obtained (Drug Trading) funds. I have NO doubt that Rush actually earned this money and paid taxes on it. It is not laundering when the source of the funds are accounted for. The only difference between transactions of cash exceeding $10,000 and not exceeding $10,000 is the reporting requirement. Neither is laundering unless the funds were illegally obtained.
No banking irregularity here.