...and depending on the chef or style of cuisine, you should watch a good chef use the tip of that drop to affect cuts on, for instance, avacados, and then smack the tip of the dropped edge into the seed and lift it out in one simple motion... It can be useful depending on it's configuration.
I really like the angles on the dropped edge as evident in the Gaucho-style knives coming from the Boys from Brazil. In this case, it's a completley different function than say the style found on a French Chef's knife or a Sushi-style knife... Like Blademan said, it makes it easier to actually sharpen the whole edge, and I like it as it forms a deep choil that is rounded enough to use without cutting into your finger...
Different uses to be sure, but the dropped edge is more than a result of the process, or it would get ground off more frequently than not...