To answer the question more specifically, Bunker costs are between a third and quarter of the operating costs of a shipping company. (Source Baltic Exchange)  I do not have an average figure for the shipping costs / retail costs - there are far too many variables.  My WAG is that shipping will be less than 25% of the final cost of even low value items. That gives a relation between bunker costs and retail price of max 6 - 7%.  i.e. A rise in fuel prices will not in itself be a major disincentive to purchasing imported plastic crap.