Aye, it's true. The populations, especially at smaller sizes are usually outside of their bounding boxes. I find this when I want a really small area population. It always needs to be re-aligned to centre the instanced objects. It's never straightforward where I can create a population and expect it to be within its own bounding box, again, this is mostly with small-scale populations, it seems.
EDIT: Small scaled, like this one, Mr L. It's only 10x10, that's where I have problems, too. It's not really annoying because it's easily centred but, it still isn't right.