Owning a gun increases the risk for homicide in the same way that owning diet soft drinks increases the risk of being morbidly obese, that owning nitroglycerine pills increases the risk of sudden heart attacks, and that going to the ER increases the risk of dying: It reverses causation.
The comedic aspect of this is that they’ll then have to supply the same warnings to most products in hardware stores, cutlery, etc.