It can be somewhat easy to forget in the heavily orchestrated world of professional wrestling, but these guys and gals are still hitting each other with a huge variety of moves, moves specifically designed to look like they are causing serious damage to those unlucky enough to get splatted with them. Real or not, professional wrestling is still supposed to give the impression of being a combat sport.
As the industry leader, World Wrestling Entertainment is in something of a strange position here. It also has by far the largest child demographic in its audience, and as such certain amendments need to be made to moves to ensure that if kids are trying them out on their friends at home, they aren't dropping each other down brain first.
Outside of WWE, brains are still getting planted however. A lot of moves we see on a frequent basis in WWE are watered down somewhat, in order to ensure a safer product for all involved. Now, no one should really need to be told that this is a very good thing; safety in wrestling should truly be encouraged. Still, we all like a bit of sickness in a moves from time to time.
Besides, how much cooler would John Cena be if it really was a Death Valley Driver...