Those things are valued for more than their resale price.
The only reason I would ever want to hold a Bitcoin is that I trust that somebody else will give me something of value for it in the future.
If governments make it very difficult for me to exchange bitcoins for other things, its utility as a "store of value" gets lower. I'd rather store my value in stocks, real estate, gold, or whatever else. The regulation directly interferes with the use case.
On the other hand, all the regulation in the world doesn't interfere with cocaine's use case of getting you high. If governments could make it so that cocaine doesn't get you high, its price would certainly plummet.
