probably because of the reason you just mentioned. EA knows that 100% of the hardcore players that will be putting countless hours into this game will use their own custom tracks anyway. the casual players most likely wont care since they'll be done w/ the game after a few weeks or so only playing sporadically during the hockey season, if that.
hey, atleast it saves EA money that they use toward making the game better like adding goalie fights!!! (end sarcasm)