I don't agree with taxing churches, per se. The people who donated their money to their churches have already paid twice: not only have they been taxed on that money, they also are doing without it. Why should it be in the negative column a third time?

On the other hand, it seems to me that the businesses the churches engage in should be fully taxable: the rentals, the clinics, the restaurants, the concerts and the myriads of other enterprises.