Abhi Shah, whose family owns the Lucky Stop store in Southwick, said Fiega scratched the ticket off while still inside the store and handed it back to Shah's mother, asking her to throw it away.
The ticket was placed on a stack behind the counter, where it remained for 10 days before Shah decided to scan the pile of supposed losing tickets.
Shah said he discovered the ticket hadn't been completely scratched off, and he completed it to discover the $1 million prize.
Shah spoke with his family, and they agreed the ticket should be returned to Fiega, who is a regular customer and well-known to the family.
"As soon as she came in, I hand her $1 million ticket and she freaked out and cried like a baby," Shah's father, Maunish, told WWLP-TV. "She sat down on the floor right here."