Ah, I see, so you meant soldiers stationed in Italy were occasionally travelling to Germany bases just to shop. But maybe this happened in coincidence with holidays, i.e. when they had relatives or people visiting them? I think a trip to Germany would have costed some money regardless, so what they may have saved on the goods would have been not much… but of course it depends on what they were buying.
Aside from the bases (of which I never thought previously), in Italy the import market for american comics re-bloomed (since the late 1960s) for some time when our local publisher (Editoriale Corno) went bankrupt and we stopped having italian editions. Exchange rates were high, but around the mid 1980s up to the early 1990s, many people started to pick the books in original edition, although most of them dropped them later on to follow the italian editions (or just because they were getting bad, as Marvel goes… ).