Jews have codified three meals a day as part of the celebration of religious days (e.g. the sabbath) since the beginning of their religion. Going to the extreme of staying someone who does not prepare for three meals has no portion in the afterlife. At the same time they were critical of gluttony.

It amazes me how people can selectively present facts to appear intelligent. There was more to the ancient world than just the Romans and Greeks. So even if they didn't eat 3 meals a day I'm pretty sure there were plenty of ancient civilisations that did.