As a new player, I am levelling up at a steady pace, but I feel that if they raised the exp needed for each level, then i'd just give up as it is. I think SE know how boring and repetitive the levelling up can be, so they aren't making you waste your time with weeks of grinding, they're letting your experience the games full potential as early as they can, because otherwise some people would just give up midway through levelling up.
.. just my opinion anyway ^^