You are correct, sir.
You can kinda get an impression of the size of those windows by comparing the worker whose picture I took a month ago in THIS POST.
There are windows on the south side where a single pane is missing, randomly. I'm not going to believe a single pane randomly missing 100 feet in the air is used to move in equipment. Sorry.
glass could have been broken in delivery. depending on the type of glass, they are not easily replaced. windows are also used to throw trash out. they'll set up a chute right to the trash dumpster. they will also be used for the intake on their propane heaters. those are just more reasons as to why there might not be any glass in the windows.