Money laundering is the act of legitimizing illegally obtained funds by passing them through various transactions to conceal their origin. The money is thereby “cleaned” of its source. This criminal practice is frequently linked to organized crime, drug trafficking, and terrorism.
“Because money laundering by its nature is a crime of concealment, the scope of money-laundering activity is not precisely known.” P102 Forensic accounting.pdf
As large amounts of money are moved over a short period of time with many events, they are attractive for criminals to launder money. An event such as a festival with entry fee can be used to change the source of the money. It appears that the money has come from ticket sales when in fact many people were allowed free entry. Over paying artist is another way to launder the money. This payment is an expense and can be claimed against the income. Over invoicing is another example. It looks as though the money has gone to suppliers.
I am surprised at where corruption is found. The art world, evidently. We, of course, know about the antique trade. But here is an idea. You buy paintings in bulk say from Iraq ( yes it is cheap and good quality). You register for a prestigious Art Fair. Then you present the work as your original ( a condition for entry as an artist) and sell them for, well, a lot.