The alternative to using a DAF is to donate directly to a charity. But there are advantages - to both the donor and the charity - to using a DAF. Not all charities are equipped to efficiently process non-cash assets like stocks, and they don't need to issue individual tax receipts for donations from DAFs. For the donor, you can bundle donations into a single tax year and parcel it out later.
But all these advantages are for naught if they refuse to send money to your preferred charities.