"Why don't you?" - because your technique/software will not be compatible with world wide techniques like Ethereum or Bitcoin exactly where ensuring uniqueness of addresses on a world scale will be the A serious aim. This is actually the question you have to be asking - (ethereum.stackexchange.com/issues/3542/�? A vanity address https://ethereumvanityaddressgene21741.blogdigy.com/the-definitive-guide-to-erc20-address-generator-45397568