For one, the concept of intrinsic value is meaningless. Value is solely subjective. If gold were merely priced based on it's industrial uses, great though they may be, it would most likely sell at less than $100/oz. It's value, like Bitcoin's, comes from it's fungibility, immutability, and scarcity. Bitcoin's "industrial/practical" application is as money, allowing us to abstract away from barter systems and increase trade efficiencies. Just as mining and securing gold require continual resource expenditures, so it is with Bitcoin. The miners, by way of solving these cryptographic problems, are verifying and securing the blockchain network. Neither are fiat, as their values arise from adoption and use, not by decree. Satoshi's whitepaper is accessible to the layman and a brief read. Highly recommended.
https://bitcoin.org/bitcoin.pdf