iPhone 3GS Battery Meter

iPhone 3GS now supports showing the battery charge level as a percentage rather than just the icon indicator.  Percentage indicator is really helpful. Most of the times I plug the charger to my macbook when it starts showing the battery level at less than 3%. And with iPhone I usually end up plugging the charger only when it shuts down completely running out of battery.  The 10% battery remaining warning is too early.

Unfortunately Apple has put this new option only in new iPhone 3GS. Its not available for iPhone 3G or the 1st gen iPhone. Apple is so cruel.

I wonder what big pain would it cause to Apple to include that feature in all iPhone models. Apple acts crazy.