"Most of the incentives that we hear talked about are actually ... not a situation where the government -- in this case, the state or local government -- is going to write a check in this case to Google," says Dr. Walden, of N.C. State University. "Instead, they are forgiveness of future taxes. So they represent taxes that won't be paid.

"Now some argue that ... if the company didn't come, there wouldn't have been any taxes to pay anyway, so we are forgiving something that we wouldn't have had anyway.

"But, be at as it may, you can look at this in a cost-benefit framework. Even if the state is forgiving taxes for Google, they may make money out of this if, for example, you account for the fact that other suppliers to Google, as well as the workers who are going to get increased taxes -- all of those folks are going to pay taxes," he concludes. "The state does try to calculate this in a benefit-cost framework. Of course it requires forecasting into the future, but you actually can come up with situations where the state and the state economy does make money with incentives."