i saw this a few days ago and some messages about this concept were actually true, basically this could never happen for many reasons
1- Danger factor - let's say you jump from a first floor to knife someone while playing using the glasses, you break your legs in real life
2- Distorted perception - i rpg a wall, it blows up and the glasses show it's destruction but in real life it's still there and i decide to run through that hole, broken nose achievement unlocked
3- fitness level - if i get shot or die, how do i spawn again? do i physically run 300m each time to our spawn point?
4- real world interactivity - so let's say i boot up the game (slip on the glasses) in an empty warehouse and during the course of the game, a bus of visiting nuns happen to arrive and decide to look around said warehouse for a future convenant site and i think that they are part of the game and go for some nun tags, this could lead to jail or worse, eternal damnation :S
in the end, our best bet for the above to become reality is neural intergation (plug me into the Matrix) for this to happen.