I think the ideas of fans being "unpleasable" or perpetual whiners incapable of gratitude is really overblown. Just look at the Mass Effect fanbase for the biggest example we've had in years. The fanbase ****ing spewed venom at the endings, but the response to Bioware's Extended Cut - which simply adds some closure and explanation without altering the endings' main points, was received very favorably. Effort goes a long way. More often than not, fanbases (fanbases, not individual fans) will only react with anger if they feel like they've gotten screwed.
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Watch and you'll see... someday I'll be... part of your world!