Those"boxes" are just part of the pass-through storage on my Mini Lite 2503S. But mine are not carpeted, they look like cabinets with countertops. The one on the curb side has a 120VAC outlet in it. My DW wanted an outlet, too, so I added one on her side.
Some of the Mini-lite/Micro-lites we saw when we were buying (Jan/Feb 2015) didn't have them at all. This pic is a Flagstaff Micro-Lite 25KS, the twin of my Rockwood Mini Lite 2503S. You can see there's no "box;" there's a carton for the TV where the "box" should be.
This pic is of a Mini Lite 2304KS. The storage door on the left is access to the "inside" of the "box."
This pic is looking straight into that door. What you're seeing is the bottom of the seat of the sofa. So you're essentially looking "through" the "box" and into the space below the sofa's seat.