can employer not pay my last check of 36-40hrs after getting fired

I cleaned restaurant hoods, many restaurants a week, rode to work every night with the boss. They were payed so much for every hood that was cleaned, but I was always paid hourly roughly $10.00 an hour, it always changed tho. A few weeks ago we cleaned a restaurant and they chose not to pay for the cleaning because I drank 4 of their beers. Now my employer won't pay me for that night or anything that was supposed to be on my check. I can understand them not wanting to pay me hours for the last job because they wasn't paid. But what about everything before that 36-40 hrs.