sure you can use bit coin,   the reason for the silver coin is in the beginning of this secret society, a time traveler had joined, photography was of a coin the time traveler had, it became political from the paranormal.  world governments tried to shut down the secret society, with only photography that the time traveler existed and the coin was from the future.  the time traveler and the silver coin caused a paradox one room turned into two.   the glow government watches all the time for the time travelers silver coin.  you can use paypal or credit card also
United States