Anybody that builds an app on a "platform" that can be taken away overnight is a fool. Facebook has made it clear that if they want to change a policy, they could care less about your "business".
Not that I disagree that it hasn't happened yet. I too find it quite annoying when people say they "could care less".
It really is suppose to be "couldn't care less". Meaning, that they are at level 0/100 of the caring meter.
But as languages go, we tend to move towards an easier way to say the same thing.
"could care less" sounds similar, means the same, and that most people associates it with the former phrase.
It’s like when someone says that the enemy was “decimated”. The prescriptivists would say that means they lost 10%. The descriptivists would say they lost a lot.
The key is level of competition or dominance. It's wise to start looking for or creating alternatives when a company has less competition and becomes more dominant. Because if its power reaches a certain point, everyone loses. The company loses cos it won't innovate any more. Customers will lose on many fronts - customer service, features, stability, price, stupid restrictions...