I believe what you have there is the not so uncommon Santa Claus button. It's a well known fact that St Nicks bright red coat is festooned with bright shiny brass buttons. A little gaudy and self promoting with the big S and all but hey, it's Santa Claus, who's gonna complain. He probably has a whole addendum in his giant book of people that have in one way or another ridiculed his garb.
It's also a well known fact that with all the physical activity, lifting, carrying goodies, his somewhat rotund physique and the fact that the poor old guy has to squeeze himself into overly tight chimneys. He does, regularly lose those big S buttons. You'll note that almost all of them are found at the bases of chimneys. Not a coincidence one thinks. Why it was only 4 years back that while cleaning my gutters, I found one in and among the rotting leaf litter. You'll also notice that they are never found at dwellings of the "not so nice" people in the neighborhood.
My advice to you would be to return it. Simply place it next to a plate of chocolate chip cookies and a glass of milk near the Christmas tree. It will be gone in the morning, but you just might find a new Garret Carrot under " ole tannenbaum".
Another coincidence ? I'd not take the chance. HoHoHo