I see the value of any currency, FIAT, crypto, or other, as based on supply and demand. As a free market advocate, did you expect anything else?

The demand for any currency grows as the currency becomes accepted by the masses and can be traded for other goods. If I can trade a FIAT US dollar for a chicken, I find value in the dollar. Over time, if the chicken costs me $100 then I may start to wonder what happened to the value of the dollar, but I know that it still has value as I can still trade it for a chicken.

The value of BTC is just starting. It may be fueled by speculation at this point, but just wait until more and more businesses start accepting BTC. When I can trade my BTC for a chicken the value of BTC will go up to me. And when the value of a BTC goes up for all consumers, because they can trade it for other consumer goods, the demand will skyrocket.

According to this site, there are around 100 decently sized retailers who accept BTC. Some are very large retailers.

When BTC goes mainstream, hold onto your seats! We are in for a wild ride!