maybe because the stubbies are all far too small and IMO, don't represent good value for money... tho per litre at those discounted prices, they do stack up as decent value.
Have to echo the comment about the Lidl pilsners - 6.95 for six 500ml bottles of Perlenbacher, brewed they say according to the German purity rules and IMO again, with a decent taste, has to be some of the very best beer value around.
Note too that these bottles can be opened by hand and have a reasealable cap - meaning that it'll keep its fizz in the fridge for a day or two in the rare event that a bottle might not get finished.