That would have been my question. The spacious studios in the big market stations sit vacant in many cases, while the night monitor wanders the halls making sure all the stations in the cluster are modulating.
The KOL building on Harbor Island (after improvements) was maybe 4,500 sq ft, and contained 2 large AM transmitters, 2 FM transmitters, 5 studios, and numerous sales cubibles along with several offices and a very ample conference room with a wet bar.
We're operating 4 stations in a 2,600 sq ft building, and we have 5 studios.
As far as dead air on a weekend, not many small market stations have anybody home. The responsibility then rests on the staff to monitor and respond. Unfortunately, not all operators listen to their own stations enough to know if there is a problem. One of the other stations in my market not infrequently has long periods of dead air interrupted only by the news at the top of the hour and a couple of spots.