A mystery indeed... LOL! There really is NO WAY that it would have left the Rogers factory assembled that way... plus! ... notice that the resonant/bottom head on your drum is an Evans, which Rogers never used/supplied... meaning ... someone had to change out the bottom head at some point in the drum's life, and that would necessitate removing the hoop with the guards attached and the snare frame of course... mystery solved! :-D Upon reassembly, the hoop was put on "backwards" with relation to the guards/butt/strainer, thus the snare frame was remounted backwards as well. Really not a problem and an EASY fix! Regardless, a beautiful and well maintained drum irrespective of the wrongly installed hoop/snare frame.
Tommyp