at all. I would guess it is "self employment tax" which is the exact same thing as Social Security and Medicaid garbage. If you are a contractor, you are the same thing as self employed. Therefore you do not have a boss that pays half of your social security garbage for you and then withholds the other half out of the paycheck. Since your neighbor was paid the full amount, he now owes both portions of the social security garbage - or in other words, he is paying for his "retirement", but I highly doubt he is paying any federal taxes.
Just wait until he makes more, then he can pay the 15% self employment tax in addition to paying real federal income taxes. Let me tell you, it's a joy.