e: pretty much this^
I think the episodic approach works in two ways:
1. It is a good way to attract potential buyers. People who aren't sold on the game (and would likely not spend the $25-$40) can try the first episode, and then buy the rest if they like it. And if they don't like it, Capcpom still makes a small amount of money.
2. It encourages a lot of time investment from the players by encouraging them to reach a certain goal in terms of collectibles, raid mode, etc. People will be consistently playing this game over the course of a month, which is probably waaaay more time spent on a primarily SP game than most.
I personally like it a lot. Ultimately I feel more investment in spending $25 for something I will get to enjoy over the course of a month rather than getting it in a single package, where I would likely blast through the campaign in two days, play raid mode for a little while longer and then be done with a week or so.