Tordan,
I believe the difference is simply philosophical. With the FBW technology there is no reason why Boeing could not have the same protections as Airbus. Boeing however have always respected in their designs the end user, in this case the pilot. In their view it is the pilot who should decide whether the aircraft requires to be operated outside the envelope rather than have that decision already made for them by a computer.
If you read the book "21st Century Jet" about the building of the B777 you will see this philosophy borne out again and again in many of the decisions that were made during the design process.