Sub-optimization rules

It is amazing how businesses resist learning from others. I see frequently that companies persist in reinventing the wheel - badly. Yesterday I was on a Delta Airlines flight. This airline boards by a large number of "zones" which seem to be assigned inorder of how much you pay for your ticket. American Airlines uses a smaller number of Zones, and while Zone 1 does consist of higher fare and premium frequent flyer members, the rest seem to flow in spacial sequence of seat assignments. Of course, Southwestm which manages to board planes faster than anyone, simply uses open seating and assigns groups by when you show up at the airport. There should logically be one solution which is best for a given profile of flight. Southwest may have a different one from an international carrier, but if two airlines are flying coast to coast, then one of the systems employed must be the best. Yet each airline invents its own.