argyle43 You're still a part of the content creation process. They still profit from your effort. Other studios pay script-writers (quite well, in fact). The industry leader shouldn't be exempt. I'm not saying pay a guy that just goes "it would be cool if I fuck a hot girl but also another hot girl" but if there is a lot of effort and detail involved, they should at the very least consider it.
There is also no guarantee that any other aspect of the production (casting, set design, scene direction, tech) will be up to snuff or even what you originally envisioned.