There’s no hypocrisy, if Epic was doing the same thing they are doing they would require you to release your games through their launcher and give them 30% profit if you want to use UE4. By allowing people to use UWP without forcing the apps to use the Microsoft store it encourages them to release their app on Microsoft platforms since it will already be compatible. For example, if I’m an indie developer then I could release on Steam plus Windows Store/Mobile/Xbox and it’d be easier than it is now. Since I don’t want to only release on Windows store, I’m not going to choose that option and I’d likely only release on Steam.
Over time, if people are that easily able to release on multiple platforms, they would end up with more apps in their store.