Because people should have freedom of conscience? If you don't believe in God, or if you're a follower of a different avatar of Abrahamic religion, for example,

Because people should have freedom of conscience? If you don't believe in God, or if you're a follower of a different avatar of Abrahamic religion, for example, why should a Muslim or Jewish homeless person have to follow a mandatory Christian program to receive "donated" shelter? Suddenly it's not charity, it's a transaction for one's soul.