So I don't see how anyone who writes fanfic can object when someone looks at a story she's written and says "I want to see more" or "I wonder if I could take it in this other direction?" Because that's what she did when she wrote her fic in the first place. I won't quite say it would be hypocritical to object, but I think it leans in that direction.
I'll say it for her, then. I think it's hypocritical, period.
If it's acceptable for us to write fanfic based on Jane Prowriter's work -- to change her ending, or have two characters she said hate each other fall in love and have wild sex, or write a sequel which completely undoes the dark consequences of her story, whatever -- without Jane's knowledge or permission, then it has to be equally acceptable to do the same thing with Mary Fanwriter's story, which is in itself based on Jane Prowriter's story. To say that it's fine for Mary to do it to Jane's work but that it's OMGEvilRudeFlameFlame!!!! for Susan Fanficcer to do it to Mary's work is just ridiculously hypocritical.
I don't buy the "It's OK because Jane will never know," bit. You don't know that Jane will never know -- maybe I'm Jane writing fanfic under a pseudonym (which we know some pros do) and I've read every story you've ever posted. What then?
Nor do I buy the, "You have to get Mary's permission because she's right here and available, but you don't have to get Jane's permission because she's way out there [waves hand] somewhere and you could never get ahold of her anyway," excuse. If Mary posted her story six years ago on FF.net and vanished from that fandom five years ago and doesn't use that e-mail address anymore, then you have no way of contacting Mary. Does that make it just fine to fic Mary's story? What if I'm Mary and I changed my nickname when I switched fandoms (as many fans do) and I'm right here, you just don't know it? Or what if I'm not and Mary left fandom completely five years ago -- does that make it all right to fic her stories? Why or why not? And does the fact that I saw any number of big name prowriters at the last WorldCon and talked to a few of them mean that I should've asked them for permission to fic their stories, and that I shouldn't touch said stories if they'd said no?
What it comes down to IMO is that the prowriters (and producers and directors, etc.) are considered to be "them." They're outside of "us" and therefore some people think they don't deserve the same courtesy. Excuses about how difficult they are to get ahold of are just hand-waving; the vast majority of them are contactable if anyone wanted to make the effort. Added to that "otherness" is the fact that the pros have something we want -- their original work, their characters and settings and ideas and story arcs -- and fanfic fans who think ficcing is objectionable (as demonstrated by the fact that they scream when it's done to their stories) and yet reallyreally want to fic the pros' stories will use any bit of sophistry they can come up with to make it acceptable for them to use those original works, and yet unacceptable for their own works to be used in the exact same way. It's all misdirection and bullshit and I have no patience for any of it.
And yes, I've been on the other side. I still hold the same beliefs.
Back when I was still writing original material, I wrote a longish narrative poem and posted it to a message board. It was a fantasy about a young man, a lord's son, who had an elven lover. The poem itself was his farewell letter to her -- his father was getting old and needed to pass his responsibilities on to his son. It was time for the son to take up a man's tasks; he was no longer a child, to be able to go romping through the meadows with his elven lover anymore. It was a bit of blatant (although obviously not blatant enough) allegory about how childhood is fun and all but eventually it's time to grow up and leave your toys behind, and that being an adult had its own satisfaction. It got a lot of positive comments and that was very cool.
But one of my fans just couldn't stand the thought that my poor protag had to give up his lover and his days of romping and playing and whatever all else they'd been getting up to before it was time for him to take over the family business. She wrote a sequel about how when the guy was old, his love came to him with an eternal youth potion. He grew young again and they went romping off together forever, yay fluffy ending.
She'd completely nullified everything I'd been trying to say with my original piece, rendering it completely pointless. And since she'd posted her piece to the same message board where I'd posted mine, she got essentially 100% saturation -- everyone who'd read mine also read hers, spreading the ruin of my story (if I saw it that way, which I did) to pretty much everyone who'd ever read it. I was furious.
And when she shyly asked me whether I'd liked her sequel, I put on a smile and said it was quite nice (which it was, basically -- she wasn't a bad writer) and that I was flattered (which I was in a way -- she'd meant it as a compliment, after all [sigh]) and she went away happy. I lied because telling her what I really thought wouldn't have accomplished anything positive, for one thing; it would've hurt her feelings to no purpose and probably spread a really horrible wank around the community, which would've benefitted no one. Also because I'd written a bit of fanfic as a teenager and knew I would probably write more in the future, and also because I had a pile of fanzines at home and planned to buy more at the next convention I attended. Objecting to this girl's ficcing of my work would've been the height of hypocrisy, since I'd been a producer of fanfic in the past and was at the time an avid consumer of same.
The bottom line here is that when I write something, I have no control over how my readers respond to it. I can't get inside their heads and put up little police barriers saying "Do Not Cross." I can't limit them to reacting only in certain ways or in certain modes. If they read and enjoy and say, "Hey, that was cool," that's great, but I can't restrict them to that response, nor would I want to. Inspiring an active response in a reader means that the writer has succeeded in communicating their ideas, and the fact that some of those responses are negative, or just not what I might personally prefer, doesn't change that. The girl who ficced my work had liked it very much, and her response was an expression of that appreciation. She meant well and it would've been petty of me to have smacked her down for it. And even if she hadn't meant well, a negative reaction is still a reaction and I still can't police what people think or feel about my work. [shrug]
If someone wants to fic one of my stories, I'm certainly not going to be hypocritical enough to gripe about it. I might or might not appreciate the result, but I'm certainly not going to try to stifle someone else's creative response to my work, any more than I'd want someone else to stifle my response to their work. It has to work both ways, always, or it doesn't work at all.
Anything less is hypocrisy.