Journals usually publish negative results from major experiments. Here's the one for LUX

http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.118...

Yea my layman understanding is that it's a social pressure to not publish the results in the first place.

It depends, lots of these experiments result in better bounds on theories. LUX for example pushed down the cross-section for WIMP dark matter below the previous measurement. That in itself is an advancement, with implications on what theories for dark matter are possible.