They might do so once. Given what chocolate might do to their livers it would probably be the only time.
A few Christmases ago, our Golden helped himself to a whole bag of Hershey Kisses, which he devoured foil wrappers and all. We called animal poison control, who instructed us on how to induce him to vomit. He was fine although he pooped red and green foil for a few days.