I see those things at Home Depot all the time. I assume that is in their design manual. The only legal way would be to bring something structural from the truss to the floor to provide support and without someone making them do it, they won't. I have seen a 2x3x24' stick of "Patio" (the aluminum they make screen cages out of) run for support. It is really pretty easy since they sell the flange for the floor connection and that could be used on top too.
I suppose the pendent drops will hinge on the wiring method and how they comply to 315.25, 210.50 etc. Usually it is just an orange cord that is not compliant. Those kinds of violations usually get caught by the fire marshal. I know when they walked around our office they cited a dozen violations. After that I got tasked with keeping the place cleaned up since I was an installation planning rep at the time.
