Why don't the grooves on an iron extend through the toe?

[alani]

There is a vertical line on the face of my irons at which the grooves start, and 5/8" of bare metal, maximum, on the toe - so why don't the grooves extend into the toe area?

 

[curtisj76]

Why would you want them? Don't think you should ever be out there should you? Toe bad, heel bad, middle good.