[smachiz]

I mean... working fine, in that the only people who buy them are pretty techy.

It's not so easy to get Win 10 working right, it requires a fair bit of effort, and the experience sucks.

I'm not so sure Steam would be super happy if Epic started distributing a new frontend and store through their marketplace. I'm quite sure they wouldn't let them.

[tpxl]

Steam sells games which require third-party launchers to work. For example: Red Dead Redemption 2 requires the Rockstar Launcher to work (many a negative steam review regarding this), and this launcher allows you to buy other Rockstar games (The GTA franchise, LA Noire and more).

So yeah, Steam definitely allows distribution of storefronts.

[rezonant]

I would be extremely surprised if Valve attempted to block Epic from doing that.

[smachiz]

Really? They specifically don't allow distribution of anything but games, which would preclude a storefront, presumably.

[int_19h]

Steam has an entire top-level category in the store for software.

https://store.steampowered.com/software

[rstat1]

They distribute games from both EA and Ubisoft that force you to use both companies launchers, that also just so happen to come with there own stores attached.