Amen! This is the only way to recover any of the billions that illegals and others working on a cash basis avoid by not paying payroll taxes.
I have a brother in law that does a minimum of $30k annually off the books cash. He never uses a credit card, doesn't deposit receipts from his business unless they are checks. When I worked for a scale manufacturer, we had a branch office in the Miami area that did a minimum of $10/week cash with drug dealers. Knowing the people running the office, the $10k was probably over 20k.