There is, however, no Federal statute mandating that a private business, a person or an organization must accept currency or coins as for payment for goods and/or services. Private businesses are free to develop their own policies on whether or not to accept cash unless there is a State law which says otherwise.
It makes no difference whether it is a "debt" or a "sale"; there is no Federal requirement that cash be accepted unless a State law says one way or another. In this case, State law is saying not to accept it. As someone living in Louisiana who rarely uses cash for anything more than a soft drink, I still think this law is yet another massive waste of legislation and I can't wait to see it stricken down.
No person shall modify the exhaust system of a motor vehicle in a manner which will amplify or increase the noise emitted by the motor of such vehicle, above that emitted by the muffler originally installed on the vehicle and the original muffler shall comply with all of the requirements of R.S. 32:352.
In plain english: Changing your exhaust system in any way that makes it louder, assuming it was legal before modification, is illegal in the state of Louisiana.
I'm sure many other states have similar laws, and I'm sure many states that have laws fail to enforce them just as here in Louisiana. I can't comment on federal laws as I have not read them personally.
Your fault -- core dumped