Photoshop Elements 8

I think this error is present in the real version of Photoshop too, but for price reasons I'm stuck with Elements for now. Here's the bug:

If you use the marquee tool (default hotkey M) to select a block of pixels, and then hold down ALT to remove part of the selection, the program behaves as expected (the selection volume is reduced). However, if you select some pixels, then nudge the content (by using the arrow keys, or the move tool (hotkey V)), this will change the subsequent behavior of ALT+selection tool, in that it will not only reduce the selection volume, but also erase any pixels that were deselected. Maybe this is by design, but if so then Adobe needs to have a stern talking to that designer.