Picking up open time does not directly affect staffing levels. It can send a "message" like you said to management but in turn then they just reassign more senior crews and adjust line values higher. Staffing at most airlines is done on block hours. While it is a tough moral subject and personally wouldn't do it I find it hard to logically throw stones at those who do...

I work for another regional and dont know exactly how eagle forms their staffing model but I am just going off of what most airlines use. Does anyone know for sure?