It's billed as a payment system and proof of being a unique human while preserving anonymity. I'm a happy user and have some free money from them. Who's being grifted here?

What do you use it for? I mean, for what kind of payments?

It sounds to me like the investors are being grifted.

So far I haven't used it for payments, I just recieved free coins some of which I changed to USD. I guess the people swapping USD for Worldcoins may regret it one day but it's their choice to buy or sell the things. So far they are doing ok - I sold for around $2 and they are now nearly $8.