In order for a number of apps to stay competitive they often give out free money bonuses to new users to help build their following. (millionairemob.com)
Think of an intro bonus as a signing bonus; in return for choosing a card, you get a little money bonus to say thank you. (simplethriftyliving.com)
The removal of the raw one - time fight money bonus from Cinematic Story Mode means there's no actual reward for playing that mode any more, since it's one of the few modes in the game that doesn't reward character EXP. (vg247.com)