[david914]

You are correct in that the doors are supposed to close to prevent the spread of fire and smoke. Wood chocks are illegal in this application because it prevents the doors from closing if the fire alarm system is activated as they should per code. The doors should release upon a general fire alarm and close (the doors should also have closers on them). Your local fire marshal or AHJ (Authority Having Jurisdiction) could write them up for having the doors held open by any other means.

You can play nice and ask that they be removed, or call the authorities on them.