This is the same for pretty much any creative endeavour unless you're established. If you want to write a book, you write it with no knowledge of whether someone will publish it or not, but until you've written it you can't offer it to them in the hopes they will. If you want to get into 3D graphics, you need to create a demo reel, spending a lot of time and effort, with no guarantees you'll be accepted for a place at the job you want. If you want to be a singer/song-writer, you have to write the songs before anyone will publish you - you can't say to a music company 'please give me a contract because I'll be great'! And indeed, having a publishing deal is no guarantee of making money. You could invest 6 months in creating a game, have a publisher take it up, float it on a download service, and find its unpopular and doesn't reimburse you enough for your effort. It's a gamble of risks versus potential gains.
I think the real focus of the professional side to XNA is university students. They have the time to invest, and it's what they want to do. XNA gives them a chance to showcase themselves, and from there to land positions in the biz. Without this platform, they'd have to go the webgame route with less, or at least more complex, opportunities to convert interest in the product to a product being sold. flOw was online for how long? How much money would That Game Company have made without being taken up by Sony and given the opportunity? Wouldn't it be beneficial for like developers to have the exposure of releasing to a YouTube games service, where players would rate it highly, it'd float to the top ten, and eager publishers scouting for the next big thing would have it brought to their attention without them either having to randomly come upon it from gaming blogs links or whatever?
