> I hope people realize that this was meant to capture interesting things and not really represent the average dinner time in the US
I'm not sure this is true. They may have not been meant to capture the typical American but I know many Americans represented in this group and I don't think it is atypical either.
Also, kudos to Nathaniel for using his dining table rather than giving into the temptation to plop down in-front of a TV since he is eating alone.
Although, all of these photos look staged. At the very least their postures were dictated by knowing they are being photographed.
If you go to the blog there are more photos http://www.loisbielefeld.com/weeknight-dinners/
Edit: looking at the other photos on the photographer's site, I think they were told not to smile. And I think the combination of lack of smiles + dark lighting contributes to the kind of depressing feel. Even for the other not-dinner-related photos on the site.
Edit 2: OMG the second photo on http://www.loisbielefeld.com/conceal-carry/ is terrifying. Never ever point a gun in the direction of another person you don't plan to shoot, people!