I have a game dev friend that told me the same thing about xbla where with the developer fee, you get 1 update/patch to a game and after that it costs something like 20-40 thousand to put another update on. I still don't understand why because it couldn't possibly cost that much to update a game when game patches are usually small?
That policy is in place to discourage developers from putting up buggy games. The idea was that the game should be tested very well before even the first submission.
Then after that, they'll have one opportunity to fix bugs.
But if there was no fee, the fear was that devs would do the minimum work to get it released, however incomplete it might be. Then fix bugs later, using the consumer as their testing lab.
Unfortunately, because many small devs don't have a lot of people that test their game, they've been doing exactly what was being discouraged. Just get the game out by a certain date. Hurry! (sometimes due to pressure from a publisher)
Then problems certainly arise.
A dev might use their free patch opportunity quickly, to show customers that they are attentive (and maybe out of some guilt from releasing a messed up game). They may have discovered bugs shortly after release, even before the complaints start coming in.
Then after that round, there are the harder to catch bugs that turn up. And the dev already used their fix.
There needs to be a middle ground.
MS still doesn't want devs to just push games that aren't finished. But MS has to understand that publishers may force that on smaller devs.