One of the more infuriating issues when it comes to writers versus illustrator is the issue of writers paying illustrators; specifically, that illustrators want to be paid right now and writers usually want to work out a split profits deal. Unfortunately, this is an area that will always be a bone of contention. I foresee this problem even if we switched to a moneyless situation a la Star Trek.
Part of the problem is that illustrators feel, rightfully, that they deserve to be paid for services rendered. Even at the most inexpensive, illustration is an expensive art, especially in the digital age. A decent computer is just a step or two below a decent gaming computer, and that can be an expensive monster. The software isn't exactly cheap either, with software packages running into the hundreds of dollars. This excludes scanners and tablets on one end, and the cost for art supplies on the other. There is also the issue of time spent, which can mean that even a black & white comic with only two or three updates a week can involves hours of work; multiply by huge factors if it is colored digitally. With that huge of investment and time, it's hard not to understand why someone would want some assurance of payment.
But...there is the writer's side as well. Writers will always be the red-headed stepchild of the art world; on one hand we are needed for any project to get off the ground, but on the other we have the least respect of any profession. Our skill is just considered too common. The problem is that people do not understand there is a difference between being able to write, and being able to write well, and that subtlety is generally lost on people. There is a lot of skill required to make a decent script, especially when it involves humor, science fiction, or a large cast of characters, especially if it is to be done well. Because of this almost total lack of respect for what we do it is hard not to get some sort of Little Man Syndrome going.
It is also not allowed that writing a script takes a lot more time than one would think. Before Word One goes down, there is a lot of work that needs to be done in terms of research, character design, deciding on the plot, how the characters will interact, so on and so forth. Attach a corporation to that design process, and it gets worse, as you need to allow for the corporation's needs and execs that want to put their fingerprints on things. Putting this into perspective, a movie production lasts fifteen months from the moment a producer orders a script made to when the last edit has been okay; of that, writing the script alone can take nine months. For television shows, production averages two weeks, of which one week is just writing it. For comics, it usually takes three or more months just to get the concepts right, and the actual script can take another month to get right. There's a reason most writers don't write more than two or three books a month. However, because the writing produces so little, it's easy to argue that it took very little time do.
The other big problem goes back to that red-headed stepchild problem. When you start looking seriously at the process, you start noticing some really weird things. The biggest of these is that illustrators usually get hired; they answer an ad or get called in, but there is an actual hiring process. That is, an illustrator is given a project and is paid for his work on that. On the other hand, writers most likely submitted a script, someone liked it, and now they want to buy it, but the writer was lucky enough to get a contract. In short, the writer had to put all of the effort into writing a script, and THEN someone pays him IF he is lucky enough. For the comics, movies, and book industries this is something that works for them, and so is unlikely to change any time soon.
Put another way: Writers get used to doing things on spec, and they have a problem seeing that others simply don't. For even professional writers, this is just the way things are done, mainly because it gives them the freedom to do what they want even when they are doing something to get paid. This is also unlikely to change any time soon; there are so many spec scripts out there, companies know that they can get away with this process. There are some exceptions, granted; Disney, for example, has a number of writer programs where graduates get hired on. But...they are exceptions, not the standard way of doing things. Crawling out of the pit of anonymity is just the way writers make a name for themselves, and it is unfortunately necessary to the process.
So...when a writer offers you a split profit deal, don't get offended because you want to get paid. We get that. We've just gotten so used to doing things on spec that it's become second nature. So just politely refuse the script and go on your way if it doesn't interest you. Unless it's another ship script based on vampires; I'm not a lawyer, but I believe you can put those people down without problem.