Did Sony Profit from the Walmart $100 Discount?

[bumidan]

So if you tweak the numbers a little bit, an incentive by Sony (in this example) to give/discount/rebate Walmart $30 (in Scenario A) for every $399 PS3 sold, turns this transaction into a profitable one ($4 profit).

However, if Scenario B is more correct, Sony (again just an example) will have to find an additional $80 to give to Walmart for this promotion to make sense ($5 profit).

If you guys have numbers for the MGS4 bundle, we can do the same calculation.