And this is how it works, its like the "Intel Inside" logo, OEM's are paid to put those stickers on there, Nvidia are using AMD's Adaptive Sync, Free Sync and then paying quite a lot of them to put the G-Sync logo on them, it makes it look like "G-Sync Everywhere" and Free Sync no where because AMD are not going to pay, and its you who are actually paying for it in the price of your GPU's.
A mate recently bought an OLED TV, G-Sync plastered all over the box, in the actual settings menu it says Free Sync 2. that's not on the box.
This is a very good point, ideally they would all be marketed as Adaptive Sync (and maybe shown as "validated" in the specs for FreeSync / GSync), in reality FreeSync and GSync are both vendor implementations of VESA Adaptive sync.