So how do you know what exactly you are hashing and how would you know if it is hashing out encrypted files or bitcoin crap? If you still got your bitcoin in your account how exactly do you know what all that hashing is working on?
I dont know much about bitcoin but I do know that if you are running a system with Intel ME it should be possible to highjack the superhashing abilities of a mining PC to work out other types of hashing.
I could be totally wrong but this was always my assumption a reason some mysterious entity would be willing to spend a load of cash to encourage what is not far off from a encryption brute forcing botnet.
You can say whatever you want but it is not outside of the realm of possibilities. A nation state actor would be well able to keep this sort of thing hidden from the miners.
Maybe not ones with ME disabled but those PCs could be left to actually hash bitcoin transactions.
Maybe it is not possible but I would need some serious proof to take it out of the realm of possibility.
Also even if it is not possible there are many other options, for example there are loads of PCs hashing for science all day and night looking for supernova ect. I use to be one of them and there was absolutely no way for me to know what my PC was doing other than to know it was doing calculations with thousands of other PCs. For all I know I was helping the NSA crack passwords.