I am curious since I served on two NFPA committees for 15 years. NFPA is a self funded non profit organization established in 1896 and has produced over 100 standards and codes addressing about everything concerning fire safety. And it may well be partly funded by insurance underwriters. But I have never heard that and am curious where to find that info.
NFPA creates documents in the form of "standards" and "codes". You are correct that the codes are not law in themselves. But they are written in a format with the proper rigidly written language to be adopted as legally enforceable codes by state or local entities or AHJs. Standards are less rigid written and more intended as guidelines.
Each standard and code has a committee of typically about 15-25 non paid volunteers who work in some way associated with that particular industry, meaning they have some expertise in the field rather than someone sitting behind a desk making up rules. In the case of the committees I served on there were representatives from the manufacturers of associated equipment, from manufacturers of associated control systems, from major engineer and consulting and construction firms, from insurance underwriters, and from the end user/customer/buyers of the products. Each group would have 2-5 members on the committee. In our case only 2 members from insurance. Prior to any proposed provision put into the codes and standards, there is a vote of members as to whether that provision is acceptable to all parties. It requires a majority vote to pass thereby preventing any individual party being able to install provisions that benefit that party without being acceptable by the majority. The end user likes more relaxed rules. Insurance likes more rigid rules. The others are typically somewhere in the middle. The final verbiage comes after much discussion and voting by all members.