ONS is using Namecoin. Namecoin isn't free to use, is it? I'm curious to know what is the business model behind this and onename.io, since they must pay to add

ONS is using Namecoin. Namecoin isn't free to use, is it? I'm curious to know what is the business model behind this and onename.io, since they must pay to add entries to the Namecoin blockchain.