It's not a cash grab. Its an optional domain registrar. Feel free to start your own smart contract based registrar. Otherwise .eth domains are accepted pretty much everywhere as a substitute for a public key. ETH addresses are 40 digits long. Yes, you can copy/paste. But having yourname.eth is nice for user friendliness. Best part though is, you have a choice. And you can always register a domain much later if you ever feel the need.