Actually yes, they very much want their tax money.
Well, what about mining?
I liken it (kind of) to farming. You need your land, your seeds, your water supply, and your machinery (or animals, which have their own up-keep) to farm. And of course, your own labor to run it, although it mostly runs itself.
You invest into those assets, and they reward you (hopefully) with more assets, your crop. Then you have to sell them (incurring costs for harvesting - labor, and transportation).
Mining coins on a PC is similar, you need electricity, internet, PCs, graphics cards, and time and effort setting them up, monitoring them, flipping breakers back to normal if you blow one, rebooting the PC if it crashes, etc.
So, if we start at nearly zero assets, we would have costs associated with buying and assembling the PCs, buying and installing the GPUs, and paying for internet, and least of all, electric power to run the thing.
So, I think that those expenses should be deductible as costs, as well as the overheat of the internet plan, and the electricity utilized. Not to mention, your labor (how does that get accounted for?).
So, a purely hypothetical, a $1000 PC, with a $500 GPU, that makes $5/day, or $150/mo. Internet costs $110/mo for gigabit, power costs $25/mo per PC, and trading fees to turn BTC into fiat, are a certain percentage.