I suppose it makes budgeting easy

It works, it makes money. It made me a lot of money. At $5,500m I was still undercharging though for the scope of what I was doing. I'm curious of the saturation point for these services. Or if there is one.

i guess it does

The initial point seems to be an understatement. Not just a lot. I'd say a ridiculous amount. Surely attesting from the demand but also the predatory/unsustainable practices of the supplier (looking at you big name agencies outsourcing to cheap overseas "freelancers").

I'm glad that it can be a business model for some talented, sane and responsible designers for a while. I seriously doubt that it scales for the clients and is a sustainable loading strategy.

I think so. The demand is always there.