People are buying BTC because they want to be rich. They are investing. Investment is one of the ways to become rich. All the millionaires have invested. None of them became millionaires by working in a shop. Investment is the way. BTC gives that opportunity. Actually, every year, many business opportunities are available. Some are very good, others are just fine. BTC are of the good opportunities to be a millionaire. In maybe 20 years, if governments accept BTC, well, we can welcome new millionaires.
Because bitcoin has it own value from the others that can help from the things that bitcoin can perform its value. It cam be more helpful and useful from it self.