Can franchisees reject a national promotion?

I'm just reading about the Burger King franchisees who are suing Burger King for instituting a money-losing promotion (the $1 double cheeseburger). And I'm wondering:

* Can the company force franchisees to run a certain promotion?

* Or do franchisees typically have the ability to pick and choose?

I guess that's partly what this lawsuit is meant to decide...but wondering how franchise agreements are typically written around these issues.