Because graphic violence only gets a game an M rating. Full nudity and sex automatically get a game an AO (Adult Only) rating. Most retailers refuse to stock AO games and getting an AO rating is effectively a death sentence for a console game since the only place you'd be able to sell them is the Internet and smaller stores. If you want big sales your game has to be sold in Walmart, Toys R Us, Gamestop etc.
Didn't The Witcher 2 get an M rating? Not that I care, I just want some consistency from the ESRB.
Maybe that's a Quebec thing?
Correct. I believe I have also seen it in Ontario (Ottawa to be exact). Out west they use the flashing green arrow for a protected turn. A flashing green light is the same as a regular green light, it just indicates that the intersection is pedestrian controlled.
Happiness is twin floppies.