What you are saying is totally irrelevant. The 7.5% raise comes DIRECTLY from the reduction in direct tax to Wal-Mart because they will not be required to pay 7.5% employee payroll tax.
Are you aware that Wal-Mart or any other profitable corporations are in 35% top tax bracket? That drops to 9% and that will leave plenty of cushion for losing deduction you listed.
Sorry, but you don't get it. Mr. Cain's plan re-defines how corporate income is calculated for tax purposes. Under his plan taxable corporate income is not the same as the taxable net income used to calculate the present corporate tax.
Right now all corporations pay a 35% tax on net profits -- which is computed by taking their gross income and subtracting the payroll they paid to employees, the amounts they paid to suppliers to buy goods, etc.
Under Mr. Cain's proposed tax plan the 9% tax is computed by taking the gross income (total sales) and subtracting only the amounts paid to suppliers for goods, money invested, and money paid to stockholders as dividends. He specifically excludes amounts paid to employees as payroll except for some "Empowerment Zones." See for yourself at his own web site.
Once you include the company's total payroll back into the "income" category, you are taxing a much larger amount of the money the company received, so even though the rate is 9% the actual tax is much larger.