Many people are shocked and dismayed to find that they're "forced" to join this AMA-thingy if they want to fly at a club field.

While the AMA is more than just insurance, most clubs require AMA membership simply because it's easier than doing all the bookwork themselves. Remember, these guys want to fly just like you, not spend 30 hours a week doing paperwork just so everone else can fly and have fun. To protect the club and flying site from being sued out of existence, everyone involved must be covered by insurance. Sure, you could purchase your own insurance, but then someone in the club would have to keep track of what kind of insurance you have, how much it covers, whether you're up to date on payments. That's a full-time job in a club with more than a few members! The AMA provides a uniform insurance policy that's good for an entire year. All you have to do is present your card, and everyone knows you're insured. On top of that, the AMA provides clubs a simple, inexpensive way of making sure the landowner is covered. Most clubs couldn't afford the insurance on their flying sites if the AMA wasn't providing a group discount. Then, where would you fly anything bigger than a park flier? Where would you fly when the local residents get you banned from flying at the school or in the park?

This is just so you know a little bit of the reasoning why you're "forced" to join AMA to fly at a club field.