I don't know what CPAs you are referring to, but that isn't what has been reported. Last month, it was reported that he has vetoed less than 0.2% spending over the past two years (millions, not billions).
CA: Governor seeks greater control over spending to avoid deficitsOpponents say the governor already can make cuts by using the line-item veto, but administration officials say its practical effects are minimal given the enormous expenditures in a $117.5 billion budget. The governor has used the line-item veto 133 times in the past two years, cutting $435,322 in spending.
I believe that they were referring not to the line item budget vetoes but the vetoes of new bills that would cost us money this year and every year on out. None of the new stuff he vetoed is free and would have costs from now to whenever. What would have been the cost of the illegal alien drivers licenses?