We aren't exactly flying over Area 51 here.
No kidding.
And as you know, someone bent on causing harm probably won't feel too guilty violating the TFR. Which makes is rather pointless, except to keep away banner planes.
Should the federal government be in the business of limiting public airspace over private companies for non-security reasons? (They don't seem to care about banner planes towing beer and alcohol ads along our beaches).
Again, I think Disney got lucky scoring this victory in post-9/11 hysteria. I don't think they'll want to draw new attention to it with some flying dragons.