A.) Privacy and legality are not strongly connected or related. Privacy is self-preservation. It is very common that you want something that someone else doesn't want. For instance, while you work at company X you may want to see if you can get a job at company Y. You don't want your current boss to know this, before you actually are sure about company Y.
B.) If you look closely the privacy here is not just defined by using the right tools. It's also usage patterns. For instance drawing money from two accounts for the same transaction gives people high confidence that the same person controls both accounts. So it's a lot tougher than "just taking the offer".
B.) If you look closely the privacy here is not just defined by using the right tools. It's also usage patterns. For instance drawing money from two accounts for the same transaction gives people high confidence that the same person controls both accounts. So it's a lot tougher than "just taking the offer".