When the Gear S3 launched, Samsung clarified that it would support Samsung Pay and it would work with any Android device running Android 4.4 KitKat and newer. It was pretty awesome news, and meant that Samsung Pay would be able to spread to tons more people, not just Samsung users.
Bad news: that was completely false information. Samsung Pay on the Gear S3 was reportedly not working with the Google Pixel, and when asked about it on Twitter, Samsung responded that the device was not compatible and it wouldn't work. Talk about getting mixed signals.
Okay, so that's really not good and will probably disappoint a few users, but there's still some hope. Samsung did follow up and say that they were always trying to expand the list of compatible devices with Samsung Pay, including through the Gear S3, and while that's definitely a canned PR response it does mean that we could see compatibility happen down the line. Probably won't be next week, but it could happen.
The next question is whether Samsung or Google is blocking Samsung Pay here. Samsung seemed pretty eager to let anyone with the new Gear S3 use Samsung Pay, so maybe it's Google that doesn't want the Pixel paired with other mobile payment solutions, especially since Android Wear and Android Pay are likely about to start working together. It'd be out of character for Google, but then again, the Pixel was out of the norm for them, too.
source: Samsung Pay (Twitter)
That is just stupid of Samsung, probably boarder lining false advertisement and a chance to get sued over it. How can it be compatible with “any android running 4.4+” but then say its not compatible with all android running 4.4+.