@ Jason - can't save state be used as training tool? Why to play first level over and over again just to explore 2nd level?
I mean, you already made it to second level, why you have to redo it again??
And as for you comment about developers, they are people as well. They made mistakes, don't they? (ever had a bug in the game?
I second andreas' opinion. Develpers had limitad space, and sometimes adding save function or pass code was unwanted (and not paid) 'extra' work as well.