Well, sprinklers in every new home didn't go down very well. Even our local code enforcement knew how much work it would be for THEM to learn the codes, and battle everyone to enforce them.
That's how I came to find out how sprinklers got into the residential codes. Seems a couple of sprinkler companies saw a vast uninterested market, so they colluded (really???) to pay hundreds of union firefighters to go to the national codes meeting that year. Free weekend, all-expenses paid in some city, I'm thinking it was Chicago, and all you had to do for it was sign in for the conference/meeting, whatever they called it, and show up in the meeting room when directed to vote yes on requiring residential sprinklers. I understand a great time was had by all, the vote to add sprinklers was strongly supported by firefighters, anxious to save lives, and it was a huge vote for safety. Every firefighter had a great holiday weekend, all-expenses paid, and residential sprinklers were added to the national codes. Easy to get in, extremely difficult to get out...
After a lot of pushback within the state, (like people wanting to see some cost-benefit analysis themselves, rather than taking the boards word for it that it was supported), it's apparently still on delay here. My brother is building a house outside the public water service area, and he isn't being required to put them in. Seems a search is on for something that costs less than 10k to install, and will reliably NOT go off till needed. They raise you homeowners insurance when you get them, because when it's wrong your stuff gets ruined.
It is so nice to see someone talking about it. I have an off the grid system too and oh my!