I agree with Ozexpatriate's analysis. Shipping costs are immaterial in the wider scheme of things. I've not checked his maths but even if he is a factor of 10 out, we'd still only be taking plus or minus a couple of quid..
Taking the point that each TEU carries several thousand units, probably accounts for why we get product in lumps over here. For example, I'd wager that the Drummond 700s, the k Pullmans, duchess variants and some new diesels all tightly packed the same one or two containers..,.