Makes sense to me. It was something someone had mentioned to me, and I had looked into it, but most of the SAR, etc. websites don't really go into detail about the benefit, and like you I kind of don't see the need to join to get a bumper sticker for something someone else did.
The main one I like to support is the 8th Air Force Memorial Assn. because grandpa was in it, and they are restoring a B-17 to fly around the country to show kids, etc.
