the answer is yes.
And to quite an extent - when I was younger, we had a butcher in the twon (Windermere) owing tax and VAT. They nailed him by asking him about his fish sales.
"Bl__dy fish, I am a butcher."
"We know you have been selling fish."
"I'm a butcher, not a fishmonger."
"At your expense, we will requisition the BBC for the proof - where is the VAT statement?"
Turned out to be that Nationwide had made a film of local characters and they showed about ten seconds of him fishing offBeech Hill for perch and trout. Then the teeniest snippet of fooage showing a tray in his butcher's window with trout on..........
He had to pay up...they were prepared to go to that extent. Also, in the restaurant trade, one of the biggest mistakes on laundering cash is to buy a fancy car, way beyond the "declared" income.......they check that one out. I have known it happen to a number of owners under "review."