I'm often astonished at how much they're willing to pay for the simplest of rush projects
This is also something that has surprised me when I initially began freelance academic writing. I didn't realize how many students were fundamentally incapable of fulfilling small tasks for whatever reason. Because of this, I struggle to fathom how they let such small tasks go in their daily calendar of things to do. Nonetheless, for as long as they pay the base, it's alright - and I know, at the end, that I'm just doing my own job.
That being said, I think that a substantive discussion would be about how these students often say that they need it as a reference essay. I do think that perhaps shame is a part of it - or, in other words, not knowing how precisely to explain that they're incapable (at the moment or for whatever reason) of accomplishing their own academic tasks. Then again, I've met a multitude of academic writers who also do not wish to admit that this the work they are doing for the same reason. I guess it can go both ways.