I could throw fuel onto the fire and say that if the cocoa bean origin is not labeled, it's almost certainly from Ghana or Ivory Coast, and therefore almost certainly a product of child slavery and human trafficking.

Having said that, as a parent myself, a couple dozen chocolates a year isn't likely to do much long term harm, and the trade-off is if a bit of chocolate/treats are demonized too hard you can be certain when she has her own autonomy when she's older she may overdo them then. Parenting decisions are often not easy.

Of course, you could also compromise by having her eat it after dinner so the sugar spike is dulled by the other food in her belly... just my two cents.