I don't particularly agree with that phrase, If you take a piece in chess I personally would say "Capture". I think the reason they say eating pieces because I believe that is what they say in checkers and I guess they think checkers and chess are similar.
My opponent eaten my pieces

This phrase is used by people who have a Romance Language (eg: French, Spanish) as their first language, since the chess term "to capture" is the same as "to eat" in those languages.

By reading the above post I want to add that this line is even used in my home state and also along the line"He is killing all my pieces" even though it was only equal exchanges of some pieces and pawn.

Perhaps they once played someone who was raised as a French or Spanish speaker, and picked up the phrase from them? Or played someone who played someone...
Certainly here in Canada, the phrase is only common among the French-Canadian players, or (sometimes) among their usual opponents.

It’s a cultural thing, been to many countries and different ones say eaten while others say captured or taken.

Perhaps they once played someone who was raised as a French or Spanish speaker, and picked up the phrase from them? Or played someone who played someone...
Certainly here in Canada, the phrase is only common among the French-Canadian players, or (sometimes) among their usual opponents.
French used to have colony in India but not in our state. The phrase told is in state language. But it is a very popular phrase in local language. French to Assamese( chuckles)
Why do some adult beginners say" My opponent eaten my pieces". How many of you support this phrase? I personally don't support this phrase. I don't think chess is a bloody dirty game. Otherwise, no country of parent would send their kids to chess. Kids are good actually good in that. They only node when we show it to them, Bless.