What evidence have you found then?
None, which was why I was asking.
I've seen tons of amphorae, which are provenanced as having been imported (with wine). Though presumably, since these are generally quite large, they had a fixed seal for a lid, and were transported via carts?
There's also the drinking horn found in the Hochdorf burial, but without some sort of closure it seems more like a drinking vessel and not one to transport drink.
I've also got some images of wooden tankards/mugs from Iron Age Britain, but once again no obvious means of closure.
Of course potential items such as "wineskin" and various animal bladders don't hold up well in the archaeological record.