Why do these “high end” gaming monitors always seem to come with free sync instead of the Nvidia G-sync. Most people willing to shell out $450 and up on a monitor are going to be running Nvidia cards which makes the feature useless. With an Nvidia card it isn’t even worth considering a monitor that doesn’t support G-sync.
The real question you should be asking is why a supposedly "high end" graphics card doesn't support a standard like VESA Adaptive-Sync, otherwise branded as FreeSync. You should be complaining on Nvidia's graphics card reviews that they still don't support the open standard for adaptive sync, not that a monitor doesn't support Nvidia's proprietary version of the technology that requires special hardware from Nvidia to do pretty much the same thing. It's not just AMD that will be supporting VESA Adaptive-Sync either, as Intel representatives have stated on at least a couple occasions that they intend to include support for it in the future, likely with their upcoming graphics cards. Microsoft's Xbox consoles also support FreeSync, albeit a less-standard implementation over HDMI.
Nvidia doesn't support it because they want to sell you an overpriced chipset as a part of your monitor, and they want you arbitrarily locked into their hardware ecosystem once competition heats up at the high-end. I suspect that even they may support it eventually though. They're just holding out so that they can price-gouge their customers as long as they can.