The Steam version is (almost?) DRM-free as well.
Big mistake :
Steam *IS* DRM !
So you cannot say "Steam is DRM-free" - because Steam IS the DRM !
It's like saying "the river is water-free".
Steam the the very first DRM fully accepted by gamers worldwide ! And big game publishers know that ! That's why UPlay and Origin exist !
Because EA & Ubi use an exactly similar DRM model like Steam uses !
Only that Valve isn't "the bad boy" !
You either haven't been gaming long, or you have really thick nostalgia glasses. Have you forgotten about copy protected floppies, code wheels, and worse; games that made you look up things in the manual randomly during the game or at level changes or to save your game? Enter the 34th word from the 5th paragraph on page 98 to continue playing the game. Then if you accidentally type the wrong word, you lose all progress.
I have an original (used" specimen of "Micro Machines" at home. It's copy protection consists of black symbols printed on vblack background ... The only way to tell both apart of that the symbols are ... glossy ? is this the right word ? ... whereas the black background is a dull black colour.
Valve owns Steam. Valve uses DRM in their own games. So, they don't hide their approach to this issue.
Half-Life 2 and Portal are made by Valve and
don't use DRM. Take a look at the
List of DRM-free games on Steam.
Since Steam = DRM, one just cannot say "DRM-free on Steam". It's like saying 1 + 1 = 3
