Could someone please tell me how you play these games? Do they give you a key for Steam or do they use some platform? Their site FAQ is not too helpful.
It's like having the Retail Disk version without the DVD. That means, you get a key that you can use to install the game from the installer files that you download. If the game have multi-player, you use the key to play online.
As I see it, their installers are like official "no-cd" patched.
You play the game without having to run any other application, like steam client.
Some games keep the DRM scheme that you get from the Retail disk version, but in other instances they are striped off DRM. If the game keep this DRM it usually noted in the game page.
For me it is like having the best of both worlds (retail/online):
I can download online, (instant gratification).
Not having to find disk to play.
Not having to run controling application like steam client
I can play offline anytime without waiting for steam approval to run the game.
I'm able to install to whatever drive I have space and not only to the drive where steam is located.