DTDC Courier & Cargo — product was broken and stolen from the package

I have sent many edible items (Imported chocolate items and gifts) as a diwali gift in delhi to my sister. She received the item on time but the chocolates were half eaten, cover packets were torn and some of big cadburies were stolen from the box.
Is that the reason these guys charge us tons of amount. What is the point of paying them if it was supposed to reach in bits and pieces. Once we parcel through their courier it is the sole responsibilty of the courier company to take care that it is reached to the said destination within time and in the exact way it was handed over to you. If you can't do so pls better to shut it down than making a fool of the public.