I understand what you mean, my point was that we shouldn't have to. :)
I know what you're saying. The opposite side of the argument would be to ask why folk should have to put up with slower, more scientifically accurate math in a game-oriented BASIC.
ie http://www.blitzbasic.com/Community/posts.php?topic=39883&hl=floating%20point%20error
It's also not like it isn't documented:
http://www.blitzbasic.com/faq/faq_entry.php?id=35
EDIT: Although, oddly, the docs in the first link and the second make slightly different claims. It would be nice to be able to switch to whichever method was required - grant you that.