The reason many companies went to eight is simple. It is a legal issue. If a company requires more time than the FAA and an employee gets popped, it opens them up to a couple different types of lawsuits. By going to eight hrs and matching the FAA Reg, it washes the companies hands of any legal recourse. Smart for them. Some saw this as a way to have four more hrs of drinking, but all it did is save someone else's six.