Magic is a very powerful and real skill that has been used for centuries by many species, including humans. The most important thing to remember about this is that magic is an obsolete and ancient form of power to those who are part of the order. This is not something that we would find any practical use for in present times, but for humans it can still be extremely useful.
The powers that the order are using are way stronger than those of any kind of magic that has been implemented on Earth. There is nothing that comes close to the psychic powers that can alter the mind and matter. Magic is basically the most archaic form of paranormal power in existence and all members of the order know this. This is why using magic would be the equivalent of a human playing with fireworks and pretending they have magical powers.