The story of the Devil Queen interested many of the players that encountered the church of light, the church reported that their goal of slaying shadow element users was due to some effort of making the goddess of light recognize their devotion but perhaps that was only the story told by the church.
Many began to theorize that the church has obvious ulterior motives.
One of the public reasons for the shadow element being banned in certain cities was easily tied to the church, it certainly made it easy to tie back to them since every city that outlawed the use of shadow magic had a heavy presence from the church.
In other regions there were actually never any signs of the reported crimes that these cities were constantly bringing up as defense for their law.