12 hours is half a day. Most players who play all of the RG's get those RG's done way before 12 hours. I don't even see the point. It already takes long enough for the Rg's to fill up, so why not be more time efficient.
It's a win-win situation. The faster RG's are available, the more money we spend. The more money we make from the RG's the more rake you get. Kapeesh?