If you really want the truth, which most people don't realize or willing to accept (or believe). Your labor is your property which is not taxable. Only profits and gains are taxable according to the IRC (Internal Revenue Code). When you (we) perform any labor (or work) for pay, you (we) are merely trading your time (your property) for pay. There is no gain or profit in the transaction.
But for the purposes of this thread (and only in the eyes of the IRS) yes, labor is taxable. Or just use cash...