Some people just don't know how to pack. This is also true for some
companies. I would first tell the seller about the shipping damage and find
out if he wants to do anything about it (maybe a discount or a replacement
if he has another). If he doesn't know his items are being damaged, I would
not expect him to improve his packaging. Afterward, I would leave positive
feedback saying something like "nice item but packaging could have been
better".