The problem is not with standard shippers. It unfortunate that people who are dependent on these barrels boxes etc didn't get them for xmas but as Nell said it's the Port Authority.
Customs is not responsible for opening containers. The Port Authority is responsible for that and can only do so when space is available. Hence the reason they request for persons to clear their goods ASAP. However over the years customers have been leaving their stuff until it's close to Christmas before clearing (the reason for that is beyond me).
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