Which is why 'nanotechnology' of the future will be (and of the past was) done with proteins & nucleic acids packed by lipids. Want to build a nanobot? Build it out of organic material. The rocks we build iPhones out of do not maintain their useful properties at the nanometer scale.
"Goddamn hacker bullshit. Looks like someone used a buffer overflow on the mainframe to encode a virus, and the thing dropped a bunch of malformed proteins while replicating in place of the data organelles. It's growing tumors and vomiting everywhere, probably cancer. We're going to have to terminate it and promote the secondary out of hibernation."
Well, we can say that we're using them. Whether systems that consume thousands of years of fossilized sunlight remain beneficial to society in the long term remains to be seen. Personally I think our systems should be steady-state instead of depletionary.
Just because we're doing it doesn't mean it's ideal.