In this scenario, the AGI systems don't need humans (you're not describing a loss in the event of humans going extinct),
Humans are a type of node of AGI. The AGI needs it's own nodes (and protocols and other stuff that makes the AGI be itself). It's not the typical AGI desire, I know - it is slightly complicated - there's more than 1 step in the thought here.
This sounds a little like Heylighen's Global Brain argument against the Singularity. We mention it, though not under the "they will need us" heading.
As Luke mentioned, I am in the process of writing "Responses to Catastrophic AGI Risk": A journal-bound summary of the AI risk problem, and a taxonomy of the societal proposals (e.g. denial of the risk, no action, legal and economic controls, differential technological development) and AI design proposals (e.g. AI confinement, chaining, Oracle AI, FAI) that have been made.
One of the categories is "They Will Need Us" - claims that AI is no big risk, because AI will always have a need of something that humans have, and that they will therefore preserve us. Currently this section is pretty empty:
But I'm certain that I've heard this claim made more often than in just those two sources. Does anyone remember having seen such arguments somewhere else? While "academically reputable" sources (papers, books) are preferred, blog posts and websites are fine as well.
Note that this claim is distinct from the claim that (due to general economic theory) it's more beneficial for the AIs to trade with us than to destroy us. We already have enough citations for that argument, what we're looking for are arguments saying that destroying humans would mean losing something essentially irreplaceable.