Who can be against a scholarship, something we normally associate with merit and achievement. And tax credits for education, that sounds nice too.
Then there are all those court decisions limiting what you can do with public money. With tax credit, you can say with a straight face that it's private money being contributed for scholarships - and the court agrees with you.
The problem is, if it really were just private money giving a charitable donation in the usual way, you would not need these complex bills to structure and regulate it and whole new state offices to administer it. And you wouldn't get to take the money back into the state treasury if its left over at the end of the year.
And you would not need to structure the program so that the funds you take back from the school, overriding the stabilization grant that the legislature put in place, in order to off-set the tax expenditure you've given businesses to subsidize the scholarships.
If the Legislature really did reject the notion of "tax expenditure" and really did agree that tax credits did not "cost" the state anything, why is the whole revenue neutral discussion necessary to get it passed?