you are not completely wrong. What you are saying is their position ( defense ) It has not been tested in Court yet. You can't indirectly waive rights though so I think their argument will fail. You have to knowingly and willingly waive rights. They can't be hidden in a contract and must be expressed clearly and a clear waiver or rights expressed
the list of problems for FB on this is huge. When they first started, they had privacy settings that allowed you full control. Step by step they changed them without new consent signed. It was left to a presumption that you agreed as long as you continued. That alone is fraudulent because when you put the original info on FB it was with an understanding you had certain privacy rights. They changed them and kept your info. Civil legal standards are based on "reasonable person" ( meaning what most people would do.) the average person is not a legal expert so their terms of service are not for a " reasonable person" to understand . Any contract requires a clear meeting of the minds and agreement. There was never a clear meeting of the minds because people didn't know what they were giving up. It was not spelled out in a clear manner.