I think anything other than the current behavior would be inconsistent.
Take, for example, C3D Points, which may have labels attached to them, too. If I use a crossing window, I would expect it to select points even if the crossing window only touched part of the label. If points got ignored unless I specifically put the crossing window AROUND the point node, it would be much more annoying, from a user perspective.
It means you can't use that method you are trying to get the results you want, but I think it is consistent with the way a crossing window should work.