100 million HODLers. Very rarely do people use Bitcoins to make purchases. When they do, over 99% of them do it through a centralized authority. The centralized authority immediate converts the Bitcoin to fiat currency, which it pays to the seller, so you aren't even really avoiding any inflationary risk. If hyperinflation of the world's reserve currencies actually does occur, there is no guarantee that Bitcoin's valuation will match inflation.
All that we're left with is a vehicle of speculation, which at best provides zero sum utility. It's actually negative sum because losing money is worse than gaining the same amount of money. Christmas lights may also people a waste of electricity, but at least everyone who sets them up presumably enjoys them or at least is doing so for someone else's enjoyment.