Right. There's no way you can provide meaningful compensation for photographers/artists from a target market of need some fairly random image/graphic for a blog post. But photographers on staff are expensive.

And even as it is, a lot of us who toyed with submitting to microstock for a bit mostly gave up. They don't even want a lot of nature/flower/landscape photography and once you've got pictures of people, you need to faff with model releases and the like--and you still don't even make beer money.