To balance things out. I too found NV to be more like an expansion. Same assets, gameplay and barely any new feature. It's basically the exact same thing, except with new locations and a new story and some slightly more polished mechanics.
I understand that it stands on it's own, that it's more faithful to the originals, blah blah blah. Still feels like an expansion.
The Mass Effect games didn't feel like expansions. They changed more things. Mass Effect 1 is very different from Mass Effect 3.
I liked F3 better in almost every way. Perhaps it's because I didn't like the original games. I understand that that can annoy you, I know it annoys me that EA has completely changed Need For Speed into something I don't like because the original games didn't sell enough...