[thetwistedpanda]

If memory serves me correctly there was a method a few years back that allowed you to create a different version of the .bsp and have clients download that version, yet it wouldn't break CRC checks. Though it's just easier to do what they've done - throw in some bad entities and let plugins strip them out. I have a few maps myself that lack all spawn points / buy zones / entities and logic as my mod re-creates them on load. Anyone that downloads the map either has to use the same mod or recreate them via another mod. It's enough to weed out the incompetent.