I've been to Christoval, TX a number of times in years gone by. I've fished in the beautiful San Saba River there.
There are flying fields where the field owner restricts use to individuals with an AMA license and a field Flying Permit.
It does seem to me that the AMA ought to offer a reasonable priced "trial membership". I think there are some folks who do not go into model flying as AMA members because of the upfront costs as it now stands. I presume we all have some concern that a model flier will do something stupid and dangerous which results in our ability to fly being restricted. I think an AMA member is less likely to be the perpatrator than a non AMA member. That is one reason I would like to see an easier path to AMA membership.