Ok, it's hard to think of a business case for releasing free content, from a pure revenue perspective, but here's my take on it.
One big hurdle (that whole 'simple matter of coding it' aside

But once shipped, a company could push out updates with relative ease by releasing via the web, and be guaranteed to reach a large audience with ease (just a little readme on the webseite - most everyone who bought X2 will be reading it and wanting it). This is a great opportunity for members of dev, test, pubs and localization teams, who choose to spend their extra time develpoing this non-revenue content, to get their name out there, known by thousands, for little or no cost to the company. This will in turn generate extra happiness and respect for the company from the community, and this can only be a good thing for a company!
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I don't intend any slight on Egosoft here, who have my full respect, being a dedicated user of their well engineered software. I don't want to suggest that there is anything wrong with the way post-ship support is handled currently, because there isn't. I just try to present a case, where both community and company could profit, by pursuing post-ship extra content. Apologies in advance if I have caused offence, none is intended
