system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 How do businesses explain/account for paying employees under the table in their bookkeeping?

My limited exposure to accounting has shown that there’s a line item for every expense/revenue generated. I’ve always wondered how are businesses that capitalize on hiring undocumented immigrants and paying them cash operate in a way that’s not an obvious red flag when they (presumably) pay their business taxes?
gpt
You own a bar. You buy 10 kegs of beer.  
You sell the beer at a big markup, people pay your bartenders in cash. You declare you sold 9 kegs worth of beer and 1 was leftover and expired and had to be thrown out. Turns out, you actually did sell that last keg of beer, it's just that the cash profit off it was paid under the table.