From Strategy Page's longer article on post traumatic stress disorder (PTSD):
It was also discovered, quite by accident, that the troop habit of playing violent video games, in between bouts of real combat, reduced combat stress. Mental health practitioners tested the use of violent video games for their PTSD patients, and found out that it worked.
In the past I went for the argument that violent games promote real-life violence. Now I see there's a strong argument that we will have a society with less violence when feelings about survival, rage, revenge, defence of your family and group, can be acted on without victims. The same seems to apply to pornography.
Scientific examination of the subject has found that as the use of porn increases, the rate of sex crimes goes down. (From "The Scientist").While I was convinced in the past that viewing sexual parts and activity promoted lascivious behaviour that threatened marriages, it also seems likely that dispersing the sex drive into play in a never-never land, reduces the drive to engage in appropriate and inappropriate sex with live partners.
Pretend behaviour seems to reduce the trouble caused by acting undesirable stuff out in real life. Be very cautious about introducing legislation to appease one crowd when the problem addressed has ambiguous outcomes.