This is a proof of attending our talk "The circular economy, ETH and ERC20 stablecoins as money. Metrics and learnings from Bitrefill, the world's leading crypto commerce company." and/or interacting with us during the ETH Barcelona conference. Our message is that to maximise the real-world utility of the Ethereum network, ETH and ERC20 stablecoins should be increasingly used as money. This also means being able to pay for goods and services.