I shifted the type of work on purpose... since I don't have a pro studio at the moment, just a little home studio, and I'm not being aggressive about acquiring new work either.
Lately, I've done some surround mixing for other people's projects, where it's already recorded and they hand me the tracks... and I'm also doing the complete soundtrack for two amatuer films, one for a friend, one for a reference through that friend.
I've done corporate work before... where they're making a training video and they need a salesy jingle, or some releveling of the audio, and some finalization. I won't call it mastering, but a lame version of that.
My personal joy is taking a band, or a vocalist, and bringing out their best, i.e. recording, mixing, mastering. This is is why I'll probably be building yet another pro studio in the warehouse eventually.
I think there is huge opportunity in what you described... and... corporations have money, and generally will reuse your services until you piss them off.