Not that I agree with Jarrod entirely on the particular information he is asking about, but fanfilms are essentially a hobby for most people, so asking for information on budgeting(a key component and the broken link in many a fanfilm's chain) in the context of the hobby is more akin to a model-builder asking another model-builder what kind of tools and paint he uses, or a cosplayer asking for tips on construction of a particularly tricky item. You're free to deny that information of course, but your framing of it as if fanfilms were competing with each other directly seems counter to the spirit of the hobby.
All in all, it's an interesting discussion.
Well, JarodRussell's post said "I see no reason why [compensation information] must be such a secret." So I tried to provide a hypothetical example of a situation where disclosing employee's compensation arrangements actually wouldn't be a good idea. Even if we decide that my scenario doesn't apply to fan films because fan films "aren't in competition," I think that there are probably other scenarios that would demonstrate why it would be disadvantages for us to reveal this information--even if competiton isn't one of the reasons.
But doubling back on my above "competitive outbidding" scenario for a moment, here's a hypothetical example:
We have an actor--let's hypothetically say she's in the role of Lieutenant Uhura--who loves acting and wants to do another Trek episode of some kind. But she only gets one week of vacation time from her "real job" each year to schlep across the country from her home to do a shoot. But she's been willing to do this for four years in a row because, well, she's a doll.
But then she's pursued by some other hypothetical Trek production to play Lieutenant Uhura.
"Come and portray 'Uhura' with us for our one-week shoot.
"No. No. I can't. I'm already Uhura with these other guys."
"Oh, come on! You can do both productions--us and them! It's not a competition!"
"No, you don't understand: I only get one week of vacation time a year. I can't do a week with you and a week with them. I can only do one week."
"Sure you can both; we're not competing. It's just a hobby--do both! You don't understand the spirit of fan films."
"Don't you get it? I don't have two weeks to give! I only have one week of vacation time a year. I can only do one! My availability to provide 'Lieutenant Uhura' services is not unlimited--whatever the true spirit of fan films might be."
"Well, then, pick us! Pick us! We'd love to have you. Is there anything we can do--all other things being equal--to get you to spend your one week with us instead of them?"
"Well, I don't get very much in the way of compensation--it's pretty bare bones. In fact, it might not even really cover my actual costs to attend the shoot. If you could beat their compensation by a bit, I might be persuaded to spend my one week per year with you instead of with them."
"Darn--if only we knew what your compensation was so that we could edge it out a bit and luer you away to join us. But I'm sure that the other guys would never have been so unprofessional and dumb as to reveal what that compensation is so we could beat it. I mean, they know that fans hate it when characters get recast. They'd try to protect that limited 'asset'."
So, if nothing else, we actually do compete with fan films--for scarcity of resources. If we were to reveal, for example, what Mr. Brian Gross' compensation is, I don't see how revealing that information publically would help us to retain him for more episodes. But maybe there's something I'm not understanding about the benefits we would experience from greater disclosure of our business practices.