In the case of stand your ground and every single other piece of gun legislation in Florida, the NRA wrote the law, and worked with ALEC to grease it through the legislature and get it passed into law in 2005, and the rate of legally justifiable homicides in Florida has tripled since then, no doubt leading more people to buy guns, no doubt leading to more profits for gun makers, and more innocent dead people.
Once the Stand your ground law was enacted in Florida, ALEC worked to get it passed in 16 additional states, using language in each case that is almost identical to that of the Florida law.
The homicidal irony here is that NRA lobbyist who crafted the original stand your ground law, Marion Hammer, when speaking to reporter Paul Flemming, thought the law did NOT apply in the Zimmerman case.