I feel like people really missed the point of the original post quoted in this thread. When people discuss SC in 5 crystal increments It should be pretty obvious from context that the point of comparison is Premium Summon vs. what you can acquire by purchasing 5 refills. Betty doesn't actually require you to spend SC for her ability to work or anything crazy like that. Her ability works automatically and the maths involved were merely demonstrating that Betty grinding is effective enough to be competitive with Premium Summons, particularly if you're fishing for silver fodder.