I don't get it ether, but I think some of it was from another story I read.  Where that if they can just 'lose weight without the sugary' then they sort of hate themselves cause they could have done it all along.    The sugary is sort of a punishment and a chance to start over.  A 'here it's not your fault now you are fixed' reset button.  I've had friends that have had it - one twice - post surgery life is no picnic.  It's not easy.  But they don't have any other choice - and it seems to lead to lots of barfing.  (eat too much it comes back up.)