Are you getting this from multiple companies or just one?
Although I've heard of such responses before, it's not the sort of response I've heard about most.
From my understanding, if editors like the book, *they* will often (not always, as in your case) be the ones to change things like that that they don't like, rather than the authors. How long was the content you submitted? If it wasn't very long I would be suspicious. If it would be entirely difficult to add that stuff in that they mentioned, it's more excusable.
It sounds like they could just be trying to glean ideas from you, without giving you compensation because they might not have liked everything about the way it was written. If it's just the one company, I recommend trying others. If you get the same from multiple others, too, then—hmm.
Have you taken their advice, and they still complained similarly? Are you /sure/ you've taken their advice? They might have meant another aspect of the meaning you received from them.
Actually, I'm personally deviating away from wanting to publish through a standard publishing company (or any, for that matter), or even submit stuff to them. It /can/ be a good route and all, but I find an increasing need to keep certain rights for myself that I know they would want to horde and stow away in a closet somewhere, unused. I wouldn't doubt if there were conspiracies going on, but I'm not about to say it's true, either. Whatever the case, it's entirely possible. They could easily control many aspects about the markets how they wanted, if they wanted (and to a certain degree, I'm sure they do this, by having certain authors write certain tales: but, where do they get the ideas for them? Perhaps from rejected authors with different writing styles. It sounds to me like this is your fear. It's possible, whether or not it's purposeful. And, of course, it's legal, seeing as you can't copyright an idea. They should at least have people sign a waver before submission.) /But/, it's not necessarily true, either—possible, but the truth is unverified, and I wouldn't waste time worrying about it.
Anyway, the whole route is insecure, even if it is the current prestigious way to get published—and out of the current ways, it's probably the one to go by unless you're willing to hold out a while longer before getting published and wait or create other successful methods (or risk a chancy one). [Don't worry, if no one else paves a way, I certainly know ways I hope to implement some day, although my methods shouldn't disrupt the traditional companies in their current way of things, seeing as they don't rely on the same economic dimension and paradigm.] You basically have to go on faith that no one will steal your ideas. Plus, even if you get published, you can sign away tons of power over your work such that you no longer have the freedom to do as you please with it (as far as such as movies, games, redistribution, audiobooks, other forms of media, etc. go)—but the publisher has the power and you have to convince or persuade them to do with your work what you want (and as often as not, it may be against company policy, anyway, or may require authorization from an untouchable source). Of course, there are lots of nice traditional publishers out there that are willing to work with authors more than that, I hope, but I wouldn't bet on it without confirmation.
Also, you have to consider that even if someone steals your ideas, you still have them yourself and you can do whatever you want with them. All they've 'stolen' is people's opinions of where the ideas came from first (if anyone is bothering to pay attention).
However, I should also note that coincidence occurs quite often—even with remarkably 'unique' ideas. There often seems to be no logical explanation. I know I've had some wild ideas, told no one, and yet I've seen them surface here and there within a couple years of the ideas' formations. Actually, as often as not, the idea was already in use a short time before I came up with it (and I certainly had never heard the idea before).
This isn't a prime example of what I'm talking about (since the idea here is simple), but, I remember back in 1999, Harry Potter was already out, I think. I saw some art for it, but that's about all I knew—and no one ever mentioned any plot details to me. I had no idea what it was about (I figured just a magical adventure story involving witches). However, I wrote a book involving a sort of school in which magic was taught. However, the mood, character, setting and background of the book was entirely different to that of the Harry Potter series—nevertheless, if I published it now, I'm sure people would construe it as a Harry Potter derivative (no matter how different it really is), and I'm sure that would grate on my nerves, seeing as the idea was new to me (although I didn't consider it 'my' idea, per se, seeing as it was such a natural and general sort of thing that I think any child in its right mind could come up with). I'll probably include the school in the rewrite—but it's not strictly necessary (however much it might seem so if you read it as is). In fact, the entire book is not strictly necessary. It could be entirely different as long as it contained a few constant parameters—but I'd rather not lose everything I wrote there, unless I publish the drafts, too.
Notwithstanding all I said above, this forum is currently targeted mainly at writing for such standard companies (though we talk about other stuff, for sure). You just said some stuff that got me started.
So, I might recommend figuring out if there is some stock in what they've been telling you. Do you really need more/less of this and that? Pull out some samples and have people critique it (samples that you're not worried about people seeing, but that will still give you an idea). You can try the critique forums here, or, I might recommend critters.org (you'd get a load of responses there—although you'd have to work at critiquing other people's stuff—but doing that should help you with your own writing style, too, and it's good mental exercise of a sort). Don't make your conclusion right away. People with more experience can see things that people with less experience don't know how to see (and this is not always, if ever, apparent to the less experienced party). Become more experienced yourself before making a true judgment.
Read a lot of books and watch the writing styles. See if you can imitate some of them.
