Because we HAVE spent all that money Square Bear, to spend it all and then get this sort of information and ignore it seems ludicrous, like running 9/10 of a marathon and giving up with the finish line in sight!
Not to mention there's how many Boeing 777's out there with a potentially fatal flaw that we haven't got the slightest clue about?
What about the lives of all those people on board, how much do you value the peace of mind for their families at?
How about for the lessons that could be learnt for potential future searches like this around the world?
I'm sure there's a lot of other reasons that people could fathom to easily justify searching an area that is backed up by CSIRO Drift Models and the Inmarsat Data now and gives up our best chance to date.