The libertarian-minded tend to think that this kind of freedom is necessary to prevent government overreach and oppression, but in reality the bulk of the people making large cash transactions are either avoiding taxes (ripping off you, the taxpayer) or participating in organized crime (human trafficking, weapons/drugs/counterfeit black markets, etc).

I would also argue that the only people making cash transactions that large are probably way wealthier than the average person and, again, are looking to launder their money.

Think about it seriously: in what scenario would you choose to use physical cash to make a transaction amounting in the thousands of dollars?

That's so insanely risky. You'd be a walking target. You could lose the money, someone could steal the money, it could be physically damaged.

It even puts you at risk during the transaction: why would the other party sell you the good when the money is right there ready to be robbed from you? There is no recourse because it's all under the table. I can't stop a check or have a paper trail to take to court if you just take my cash.

There is no situation I would be comfortable making a transaction with that much cash (unless I was in so insanely wealthy that this amount of money meant nothing to me).