Some additional information on our experience in October may help clarify (or further confuse) the discussion. Where our card was used the merchants (including Grand Marche, Simple market, Petit Casino market, and a few others) had no reservation accepting it. However, several other places (including Bikini Beach, and two of the outdoor cafes a few doors down from Petit Casino) were cash only. Obviously establishments are handling the chip card issue differently.
Also, where our card was accepted the cashier took the card and swiped it behind the counter so we did not insert it in the chip reader like we are doing now that we got back home.