They can only do that on HBD that are in the system. Once it gets out (PolyCUB -- cough cough) it will likely not come back in easily.

Of course HIVE does control the supply and down the road there may be a situation where most HBD is traded off chain. Maybe that is the goal. I don't know and don't have the chops to game out the scenarios. Maybe @smooth could speak to this ;-)

I personally think having HBD out in the world trading and being spent would be a great thing for the future of the coin, but what do I know.

Oh. Yes I think it would be good if they came off of the fee somewhat :-)