Yes, I was thinking along the same route, something waterbased like crayola markers, crayons, paint. You'll probably lose spikes if someone spills something or the floor is mopped.
But, it beats risking dancer's safety, or having to respike every day.
I know there's some Artline markers I used that don't get out very easy. They're semi-permanent, and you have to scrub them off, but they did come off with hot soapy water and a scrub brush. I only know this because my friend's son got a hold of them and decided to do his school project on my floor. I got them at Dick Blick Art Supply. If you went that route, I'd make a tiny not so obvious mark in the corner somewhere, wait a day, and try to scrub it off to make sure it would come off your floor. That's probably not the easiest route though because you'd probably have to scrub every little spike every time the director changed their mind.