I can't remember who but it was someone here who said that the max inflation printed on tire is the result of an argument between the marketing people (who want a higher number there because the racers willing to pay $$$ for tires want to put 140 psi in there) and the legal people (who don't want to be sued because people see their tires poppin' off their rims when they're too inflated).

Made a lot of sense.