Yes, it gives you a discount on trading and can be used to buy things from FTX, and it was originally a fundraising mechanism.

Why does anyone create their own token? Once you get people using it, then you can just "print more" and make yourself incredibly rich. Creating wealth out of nothing but people like your foobar token and they will convert other tokens to/from it. You can sell it to sell fake equity (without usual oversight) in a company too.