We don't really need BTC. I hate when I see people trying to convince others to sell everything they have to buy BTC, it's disgusting. Bitcoin is a lottery, you shouldn't use the money you need to pay your bills and buy food to bet in the lottery right? Bitcoin is kinda the same thing. People should invest money that in case they lost it wouldn't be a big deal you know? It's a long-term investment, however, it's a bet. You can win a lot or you can lose a lot too. Are you brave enough to deal with this risk?
Everybody uses bitcoin because of its benefits. It has many advantages that many people desperately need. When you withdraw money from regular workplaces online, the bank will keep your money for a few days. Similarly, international bank transfers can take quite a long time. Bitcoin transactions, however, are much faster.