I think you should ask an accountant to be sure. Usually if you earn below a certain amount the government gives it back in the form of a refund.
I always wonder why some businesses only ask for cash payment. For example, there is a well known restaurant that only accepts cash from its patrons. The restaurant is called Le Tub and it is famous for its steak burgers.
As a matter of fact it was featured in Maxim magazine as one of the best places to eat a burger in the United States. It just makes me wonder if they report all of their earned income.