Grub Menu Colors

Not really a problem, but a question that's got me puzzled. At the top of the menu.lst file are the lines:

timeout 15
color cyan/blue white/blue
foreground ffffff
background 0639a1

I was wondering what the necessity was for the last two lines. I know they represent colors in hex format; the 'ffffff' being white and the '0639a1' some sort of dull greeny-blue. But surely all the information for the menu colors is in the second line;
normal foreground-cyan, normal background-blue, highlighted fg-white etc.

I've noticed the menu.lst files in other distros (Ubuntu, Knoppix) don't contain these lines.

If someone could provide an explanation I'd be very grateful.