While a great many of us have now migrated to using Windows 10 (it's hard to argue with the price of Free), I doubt many of us would own up to using the Windows 10 integrated store on a regular basis. It has rightfully developed a reputation for being hard to navigate, filed with shovelware and fluff items, and generally charging higher than rival storefronts.
Games bought on Microsoft's own store do sometimes boast one perk though: Cross-platform play (and often purchase) with Xbox One owners. That's exactly the case now for ARK: Survival Evolved, making its second PC debut for those who want to keep up with their Xbox-owning friends, or a new port of call for those who don't mind a little platform-hopping.
In a bizarre decision, the Windows 10 store version of the game runs on a slightly different engine to the Steam edition, meaning that new features are likely going to be rolled out on the Steam version first, before reaching Windows 10 & Xbox, which are effectively their own ecosystem. On the plus side this means that it also makes it a cross-buy title, as you're effectively buying the Xbox One version of the game to play on PC, but it does mean that there are some barriers still up between the Windows 10 Store and Steam-bought versions of the game.
There are some additional restrictions to cross-platform play. Windows 10 players can't just freely join any Xbox server, but rather have to find one with the specific cross-platform play enabled. A sensible decision for competitive balance's sake, but I can't help but feel this might divide an already niche market within a niche further. While the game retains a very healthy number of players on Steam, I can't imagine too many will be buying the game for the first time on the Windows store, especially as the game costs a full $60 there, but is a mere $23 on Steam at present.
It's always nice to see cross-platform support offered - the fewer boundaries there are between PC and console players, the better - but I can't help but feel that this is a feature that has come far too late to draw anyone away from the PC version, and while I'm sure there will be some starting on Xbox and using the cross-buy option to migrate to PC, they're going to find themselves running a parallel codebase to the rest of the active players.