Google Fi (in the US, at least) is $10/GB. So 1000mb is $10, or $.01 per mb. It'd be only $.0139 on Fi.
That's quite a huge difference. The chart even says that US data would be $.09 which is still hugely different.
It claims to use the cheapest plan from the dominant carrier in the country. That doesn't mean that everyone is getting screwed like this, just most people.
They say they get the prices from ITU, but I don't know where on ITU they found that data, but I feel like maybe something is being used wrong.