But yet as a developer "i don't write good enough code, so we have a massive test harness to catch any bugs I might introduce".

Of course the goal is to operate at 100% efficiency, but in reality that's not going to happen all the time. Backfill channels like this are a way to make at least a little bit of money when sales a slow for a bit for whatever reason.

In terms of the problems the online media industry faces with advertising, the efficiency of in-house sales teams is not a huge priority atm.