[SeanLuke]

Italian methods for cheesemaking are nearly identical to US methods (including, in most cases, pasteurization). I can't think of any cheese preparation differences that would have the slightest effect on lactose. It is the case that Italians eat more sheep milk cheese (pecorino) than Americans, and sheep milk has a bit less lactose. And Italians also eat more aged cheeses. But I don't think this is nearly enough to explain any differences you may have seen.