If you sign up for a Web3 social network or chat room or trading venue or let’s-buy-the-Constitution lark, you will get some of that project’s tokens, which will entitle you to use the project’s app or exchange or Constitution, and which will give you some notional say in the decentralized governance of the project. Also the tokens will appreciate in value if the project takes off and more people want to use it. It’s as if being an early user of Facebook or Uber also automatically made you a shareholder of Facebook or Uber, and when those services got huge you got rich.