That's expensive. You have to have someone do all that paerwork, the paperwork has to exist (printing and doc management), and there needs to be a hard copy of the business agreement on a per customer basis.

I mean, I'm kinda old timey, so ot"s not infeasible from my point of view; but in today's hyper-optimized, bottom-line over-fault-tolerance world, I don't see that happen all that much.

Heck, I have trouble getting a straight answer out of the youngin's to "What is a filing system?"