"Is there a statute of limitations on grand-theft-nuggets?" one commenter joked.
"I hope so because I calculated it and I would owe Ronald about $NZ1888 (CA$1600)," Mr Bondarchuk responded.
He said he'd worked at a McDonald's that had been mostly visited by drive-through customers, and had never received a thank you for the extra food he had handed out.
"But I'd like to imagine (the customers) went home, saw the extra nug, and smiled a little," he said in another tweet.
One wrote: "Are you working at a bank now and if so which branch?"
The confession prompted other former Macca's employees to make similar confessions of slipping extra nuggets into ten packs over the years.
The tweet has been liked 832,000 times and retweeted more than 72,000 times.