You're taking it to an extreme. You think that just because Sony does not sell the A580 here and instead focused on releasing it in HK, China and the USA, the big markets, that they are pulling out of SG entirely? What utter and total rubbish nonsense.
Think of it as basic maths:
1. Let's say that out of every 100 DSLR cameras, sony can sell 95 A55 units and 5 A580 units (remember, it's the A55 getting all the press). So it makes sense for Sony to put more production on the A55.
2. Now, remember that Sony has guaranteed supply contracts with Nikon for the D7000 and Pentax.
3. So if Sony only has so many sensors left over, why create and maintain 2 separate product lines in a relatively small market, when it it already totally selling out of A55 and A580 units in Hong Kong and the USA? Why divert supplies from already sold-out markets to a small market? Makes no business sense.
If Sony had more production capacity (and they are in the middle of expanding, remember), they would produce more A55 and A580 and then supply to more markets. But as it is now, their supplies are constrained, so they have to focus on the markets they *know* are selling well.