Its called inflation, you are assuming the extra $80 a week is consistent with CURRENT price levels. Simple Econ 101 proves this theory wrong. Demand and supply curve will shift when outside forces increase prices or limit supply.

The extra cost the business incurs is directly passed onto the worker/consumer in the form of higher prices.

$7/hr might allow you to buy a $50 PS3 game. If the company making that PS3 game has to pay workers 2$/hr more, that game becomes $60, the result of the increased wage results in increased prices aka INFLATION.

Let me make it simpler:

Obama , instead of passing the Stimulus Bill, decides to just mail every family $500,000 in cash, merry xmas. Now, every person in america can go buy a z06 for $80k. you think chevy will keep the price of their Z06 at $80k? Absolutely not. They will raise prices on their goods to a new equilibrium.

If everyone made $100,000 a year you think a GTR would still cost $70K? Gallon of milk would cost $3?