Ann: Company Update, page-67

Wine barrels wouldn't get shipped around. For international shipping much more cost effective per bottle to send them
in a special bladder inside a shipping container like this. Took this photo not too long ago. Worlds biggest goonbags, >30,000 bottles per container. this is how they get over to the UK market your referring to.

Even high end wines like Penfolds, Wynns etc get maturation in the barrel at the winery, then get blended together and then put in a bulk tanker and taken to the bottling plant. Transporting per barrel is just too cost prohibitive