Having things cost more isn't an issue if the economy grows at relatively the same rate as the nation's money supply. For the economy to be considered inflation

Having things cost more isn't an issue if the economy grows at relatively the same rate as the nation's money supply. For the economy to be considered inflationary, the money supply has to outgrow economic growth. The OP is making the argument (at least how I interpret it) that economic growth has been stagnant, and that the money supply hasn't been effectively put to work in the real economy. The US inflation rates are more a reflection of central bank activity vs the actual economy (which is deflationary).