Why can’t you just pay the nodes dollars for their services? Why incentivise the nodes with cryptocurrencies?

Blockchain
#1

Much like the internet, the blockchain infrastructure runs across the globe with millions of nodes writing billions of new records every second i.e. it is a decentralized system. This ensures that the blockchain infrastructure does not have a single point of failure, which could otherwise threaten the entire infrastructure.

These nodes are paid fractions of a dollar for every micro-transaction. It is impossible to use the existing fiat money infrastructure to make real-time, micro-payments to millions of nodes across the world. Fiat money payments have to pass through intermediaries such as banks, money changers, card networks etc., and are subject to friction, delays, exchange rate fluctuations, transfer charges, and other cost inefficiencies.