It might be Fun Pimps inspiration, but I, personally, don't see it. One might say that the one thing The Walking Dead introduced into the theme was that humans are bigger threats than zombies, though, honestly, that's the case on almost every zombie movie I can recall. But, I'll grant it, never as prominently as on The Walking Dead.
Are humans the bigger threat in 7 Days to Die? Well, if so, then there's truly a lot of development to come, though it does seem that alpha 17 is going in that direction. And maybe that's the case on multiplayer -- I couldn't tell. As far as single player goes, though, I just don't see any influence whatsoever from TWD.
Post-apocalyptic games and movies seem to be a much stronger influence, even stronger than zombie movies. The "base" concept is a traditional staple of zombie movies, though usually as "prefab" adaptations, so to speak.

And the idea that zombies eventually find a way of wrecking your perfect base.