Why do we need initiatives to be "faith-based"? Why can't they be
done because it's the right thing for society to do?

They say they are doing God's work. I agree with you though, and I think 'good deeds' have an infinitely greater social value if done for their own sake rather than with the seemingly unnecessary excuse of religion. Although a lot of good is done at ground level by religions, and not always conditionally, the people doing it are generally under the illusion that it's their faith that makes it happen. Why anyone would need such an excuse just to be a good person, I've no idea.. Not low self-esteem, that's for sure. It's not even a good excuse - Hitler said on several occasions that he was doing God's work. It was the same illusion.