That's how government works; there are lots of things that the government uses our taxpayer dollars for that I do not agree with, but that's part of the social contract.

As long as providing financial preference to a religion serves a legitimate government purpose, there's nothing unconstitutional about it.  The Bill of Rights was created to protect the People from government not prevent the government from assisting.  Look at all the money that goes to NPR but not to Fox News.  That's government support of free speech of one sort over another.  No one's whining about the constitutionality of that.