That's not a bad idea Na, although thinking about it. I can see it could be rather costly, unless they were able to get a load of 'klik' interlocking flooring, fell off a back of a truck. There again they may be aquired as an item or job lot, that could be picked up at a Salvage yard or Auction from time to time!
They would work, even with painting the surface & they would certainly be able to strike them on a Bump Out.
However I have seen old rolls of'Tarquette' & 'Marley' Dance mats used to cover the stage & even paint. They give a great surface for dance & movement. Though not very robust for stage works & mounting sets on. We adopted the same method of under gaffer taping sheets of MDF, to cover the whole deck & paint. Using the gaffer tape, which joins the sheets together from under neath, made it very easy to remove & even to relay again another day.
I have also covered sheeting like MDF or Masonite with unbleached calico, in a 'Gesso' method, which gives a textured surface, that is good for an average box set.