Rae,
I'm going to suggest you re-think your opinion of the AMA. The AMA seems to have a lot more interest in assuring their corporate cash flow than in supporting those flying multirotors. Having been a member,until recently, for over 25 years I've observed their actions closely. Back in 2007 I was helping one of their district VP's remain up to date with what was happening in the UAV world. He was informed of the formation of an upcoming ARC committee that would be establishing the federal path forward for U.S. UAV operations, and RC modeling was going to be an area heavily impacted. He related that information to the AMA to no avail. When the ARC committee was finally formed the AMA had not made any contact with them. By the time they did they were only permitted to attend the meetings and listen, bound by a non disclosure agreement not to share what they had heard, and were not permitted to provide input. That decision should have been fought long and hard.
By the time the FAA's model registration law was enacted the AMA did little to fight it. For the most part they suggested modelers sit and wait for the final registration deadline before doing anything at all. When a private individual sued the FAA to overturn the registration rule the AMA did not jump in to assist. The rule incorporated a clause that modelers fly within the rules of a national community based organization, which they presumed meant the AMA. Having that clause meant the AMA membership would likely increase if people thought they would have to be a member of that organization in order to be in compliance. That was just perfect for the AMA as they had recently done an advertising campaign to increase their membership in order to appear stronger as a group and to help defend against the newly proposed rules. Immediately after increasing the membership by a substantial number they increased the annual dues. The AMA was not happy to find they were not specifically named THE national community based organization, which meant that anyone that formed a new organization, developed a few safety rules, posted them on the internet, and obtained some number of members instantly became a "national community based organization". In fact, they went one better and became an international organization. You could throw the word "recognized" into the fray but the regs never referenced who was required to "recognize" the organization.
The AMA is far more interested in promoting amateur aero modeling competition at both the national and international levels, generating as much revenue as possible to maintain corporate management structure, being a place where long time industry leaders can retire to as AMA management and still receive personal income after leaving their RC hobby businesses behind, than they are in multirotor operations. They pay a little lip service to them by accepting multirotor advertising dollars and allowing an occasional article in their magazine but where promotion and defense of multirotors ops are concerned their actions are few and shallow. Take a hard look at the rule differences between PArt 336 and 107 and you'll see where pretty much nobody but individuals had any impact in how the rules were defined. Although the equipment used between amateurs and professionals is more often than not the same the professional is severely limited while the amateur almost has carte blanche in what they can do and get away with. The only real limitation for the amateur flyer comes from the "careless and reckless operation of an aircraft" clause in the FAR's. Realistically the AOPA is doing more for sUAS operations in the U.S. than the AMA. Also bear in mind the AMA charter designation prohibits political lobbying.