Great point! For what it's worth, they could easily spend more than that $1.5 billion. Or at least cause to be spent. There's well known theft of electricity and computation for mining. Give the opaqueness of the industry, it's totally plausible that there are under-the-table deals or power diversions at large scale. Some people will be in the grip of sunk-cost fallacy or irrational optimism about Bitcoin's future gains. And then of course there are the negative externalities from things like pollution.