If you submit your work for free, to be viewed or read for free, they break the law by charging for it & making money on it without your permission. In this case, I'd demand 50% of everything it took in so far, & 50% of everything they take in on it in the future. If they refuse, sue them for several million dollars. You'll find they'll be more willing to negotiate rather than go to court if they get a letter from your attorney.
Please note, you want 50% of what it took in, not 50% of profits. If you ask for 50% of profits, they'll juggle the books to show they only made 5 cents or less per copy on it... after they pay their staff & themselves $20 or more per hour each.
In the fine print when you submitted a story there, it might have said you gave permission to do whatever they want with your story. In most cases, that implies whatever they want, at the site you submitted it. You were intentionally misled, which is illegal. Fancy, deliberately confusing or misleading agreements or contracts are no longer legally binding anymore these days.
You did not intend or expect someone to publish your work in an e-book for money when you submitted it, & it was not implied in the agreement.
When you post a story at Betty's you're giving permission for Betty's to carry the story, & archive it to repost at Betty's later someday. That doesn't give us or others a right to repost or publish your story at other sites or places or charge for them without the author's permission.
We actually go after people who repost or publish stories posted at Betty's at other places without the author's permission. If they're published from a country or server where the law can't touch them, or they can ignore the law there, there are other tricks & web tricks to make things miserable for them, or bring the site down.
So far many of our authors didn't mind their story getting published at other sites without their permission, as long as it wasn't altered, & they still give the original author's name or pen name (author's web alias). But seriously, I'd draw the line when they start publishing it in a book or e-book, or charging money for it, while you're not getting a cent.
At some point by being silent about it, after they've published it long enough, they start claiming it's their story, & turn around to sue you for publishing or posting your own story. They'll literally dare you to try to prove it's your story anymore, & try to make more money off of it by suing you.
By posting stories at Betty's you are creating extra evidence that you actually own the story, & evidence that the author name/pen name/web alias is really you.
Maybe you should post the stolen story at our stories, so they can't make any money on it. Most people have no problems finding our stories site, & can easily find the theme or situation they like through our search system there. Let's see them just dare to try to demand we remove a story they're charging for that was posted here by the original author for free.
I don't mind PDQ & other sites or stores trying to earn a living or make a profit in the sissy & ABDL business by selling great, fun, or useful products to us. Just don't cheat, steal, over charge us, or lie to us, because one of Betty's sites jobs in the community is to report it, & try to make them stop that kind of crap.
We got accused of "stealing" occasionally in a gallery once in a while. Under "far use" laws, most courts will agree if less than 10% of the material is used, no laws were broken. So gallery of 70 or more pictures, if 1 or 2 came from another site of hundreds, it is within "fair use". Then in most cases the original is a much larger 60kb to over 1200kb image where our post is a smaller highly compressed version of 6kb to 30kb. People still have to go to their site to see the image in full size & quality, & see more of their images.
Also some of those places should actually talk to the creator of the image. Sometimes the originator gave permission to us, or did not give them permission to post the image either.
I have to say though, many of the pictures I have no idea where they came from. Some of them I may have had saved many years ago, so don't remember where they came from. I also still use the usenet (newsgroups) for a lot of my image sources. Then there's countless sites, groups, image sites, & Facebook reposting pix from everywhere. Most of those places aren't specific as to where the images originally came from, so I don't know either.
Sometimes I recognize the style, person, or the image, so know the source. But most of the time I don't know or don't remember. That's why it's always good to post smaller, compressed versions of images along with many other images from other sources. That way we can claim "fair use" because the material only makes up a very small portion of their collection, & is only a small amount of the total gallery we posted it in.
As far as TV & movie captures... most of them were originally 24 or more frames per second, where the whole video is 20 minutes or more long. That's at least 28,800 frames for a short 20 minute TV show (modern 30 minute TV shows are 20 minutes long after the commercials are gone). We'd have to post 2,880 frames of the same show to reach the "fair use" limit. So a dozen or a few hundred frames of a video is well withing "fair use".
So posting a paragraph out of 100 paragraphs of a story, script or written work without the author's permission is legal in most courts. But if you submit a story to a site, & the agreement states you gave them permission to do what they want with the story, it is assumed by law that "what they want" is for within the site. The agreement does not give them a legal right to publish your work in a book, e-book, or sell it.