If charities and other not-for-profit organizations have tax exempt status, then I see no reason for churches to not have it.
Good point. Should just get rid of tax-exempt status. But especially for churches.
Really, for the most part, churches are a better use of tax-exempt status than other not-for-profit entitites, including charities. Typically, church donations are used to pay the minister about $30,000, maintain the church and the minister's property, and support local and national charity causes. If you want to support the poor in your local area, you really couldn't do a whole lot better than giving to the right church. There are exceptions to every case, of course. Some churches are nothing more than a money racket, and others are in such poor shape that nearly all of the donations they receive go to building maintenance.