"Desktop" games in windows store?

Will there be desktop games in windows store?

I saw that 18+ games will not be allowed there, but will I, for example, be one day able to download Civ5 from the store?

I'm looking for an alternative to steam so that is why I ask this. So far I found GOG, which fulfills all my insane paranoid needs, but they still don't have that big a library.