There are a lot of things a company can do, but usually there is one that maximises your return on equity because that's what you are good at. Sure any company with capital could run an insurance but maybe some other would be better at ?Without the money to show you can pay claims from somebody you cannot get approved in any of the 50 states or in any first or second world country. As for expertise when insurance carriers first started writing this coverage they had no date and put programs together solely on what the dive industry could offer. Now they have enough data to actually based on their own loss experience to better understand their risk from an insurance standpoint.
Maybe PADI is better at running their business than running an insurance ?
I have been working in pension reinsurance for quite a while and everybody can learn how to read a mortality table but that's not because you can read a few numbers that you can start a pension reinsurance company.