Actually, some people might not be very good at FPS' and think that VATS balance's it all out.
In that case, why are they playing an FPS in the first place if it's not their cup of tea?
I'd say that's true of me. Trying to keep my cursor centered on an enemy while both of us are in motion and bullets are flying everywhere is not something I'm overly fond of. As such, it's not something I'm very good at. VATS saves me from the real-time paradox of my
character having 100 in Small Guns while
I still can't manage to hit anything close to that level of skill. For me, when my VATS meter recharges, I don't look at it as "cool, time to enter cheat mode," but "hey, now I actually get to roleplay within the abilities of this character I've made." :shrug:
To the second part - just because something's not catering to my own personal tastes doesn't mean I can't accept it as a quality game, or that it will keep me from enjoying a game that otherwise I wouldn't have. I'm not too big into action-y games, but I've had loads of fun with Batman: Arkham Asylum, Assassin's Creed, GTA, etc. I might get frustrated in GTA sooner than someone who's been playing lots of shooters would, and play for shorter periods of time - but I still had a blast with pretty every game in the series, there.
Plus, even if it is a game I don't feel like playing - I can still admit it's quality. I'm just not that into Halo, but I can see that it's a quality title with a lot of polish and professionalism going into it.
Anyway, back to the VATS thing - I tend to think of it as an Aimed Shot (which is what it was back when Fallout was turn-based...) There did used to be a trade-off, however. You had to balance the increased chance of a critical and (potentially) better accuracy against the disadvantages of using up more Action Points to do it. I don't know what they should do with VATS to bring back that interplay of tactical choices, but it would be a nice element to toy with (and would likely abate - to some degree - the complaints of those who feel it's overpowered at the moment.)