I don't know why people are "dumping" them bcoz of the "problem" stated here ... but it's funny that a similar post on Nikonrumors showed up about Canon 5D MK III ... I think it's more of a perception rather than fact ... while its true that D800 needs high end glass at 36MP, one can still use mid range lenses on D800 at lower resolutions (24MP etc) to get great images while handholding.
Wouldn't that defeat the entire objective of buying a D800 in the first place?
No it does not.
I have a 16-35 f/2.8 L lens, but the vast majority of the pics taken are at f/16.
Most cars, in the country I currently live in, can do 240kms per hour, but no one ever drives over 140kms.
Canon cameras/lenses are my primary source of photography but I also use a Nikon D7000 & 18-300 VR lens as it comes in very handy at times but that does not mean it defeats the purpose of having a 5D MK III.
If someone already has several Nikkor lenses, D800 at a price point that is much below 5D MK III makes a lot of sense ... if one shoots at 24MP, the D800 gives similar high ISO performance (if not better) of 5D MK III.
People who "dump" D800 bcoz their mid range Nikkor lenses cannot handle resolutions at 36MP, don't know much about how to use their equipment. Every single Camera/lens has some drawback, a good photographer works around those drawbacks and concentrates on taking advantage of its strengths.