It is possible Fuji merely wants enough preorders to justify a large first production run of bodies and lenses.
Those who are willing to preorder a camera at this price-point which has not yet made it out into the wild are, presumably, a small but telling indicator of how well the cameras is likely to do in, say, the first year.
A large sell through also builds buzz. Those willing to invest so early (or who are willing to be pushed over the edge by a strong discount) are some mix of innovators and early adopters. The camera and Fuji are known quantities and Fuji has demonstrated a strong commitment to solving problems and providing innovative upgrades through its generous firmware practices, so it isn't completely the bleeding edge, but it's still a big move.
So yes, maybe there will be bigger discounts, or maybe they are simply priming the pump and the rest will just follow the natural life cycle. I'm not sure the price has to drop on the 50r if the 50-pair just takes its place as the smaller, lower cost entry and the 100s becomes the flagship.
Time will tell.