they do that in much of the northeast - its a way to feed more money into the teachers unions. the property tax is primarily composed of school taxes, which have been rising 3x the inflation rate as teachers/administrators salaries and pensions zoom. the state raises broader based taxes, and kicks some of that money back to defray the impact of the school tax increases, to calm the sheeple from rebelling against the public education complex.
As I was a taxpayer in Pennsylvania for 35 years, I am well aware of the horrendous school taxes. I never remember them giving anything back though - just more increases. The school tax never, in that time, remained the same or decreased, despite adding a state income tax, local income taxes for the schools, and legalizing gambling through the lottery and horse racing.