>> It is lying to make a blanket statement like "in stock" when you know there is a fair chance that it isn't.

Well, hold on. They're not intentionally lying. They are allowing a condition where an inaccuracy could present itself, but is that lying? That is the last information that the system has. I suppose we could always use UX labeling that doesn't imply any commitment, i.e. "Reported in stock" or "In stock at last check" and that would be more strictly accurate. I wonder how users would react?