It's not the clubs who write out the insurance policy. As far as where the costs are,

"it means you have to keep track of every single member and every single plane, and every single component in every single plane. You have to have a set risk factor for every combination of components. You have to assess the area in which they will be flying for public risk etc etc etc.. And you have to have people on call to input changes to that database and figure rate quotes. Huge technology and administrative costs would be involved."

You bring up annother cost though. The club has to somehow make sure you do have the proper insurance for the plane you are flying. So instead of the AMA issuing you gerneric AMA member card, it will have to list exactly what you are insured to fly.