[MarkMc]

Yes, I agree there can be unethical behaviour that is still lawful. But regarding the specific charge of deception it becomes much harder to convict Facebook if the company has done everything that they explicitly agreed to do.

In this particular case I cannot even see any shade of grey. I apply for a credit card. The application form states that the credit card company may pass the information about me to third parties. The credit card company tells Facebook my income. Facebook does not reveal to me that they know my income. Where is the deception?