Grips on German bows - why?

[Thomas Erickson]

So what's the story - obviously a grip is going to add a little weight, so if one is added or removed it will change the balance of the bow a bit - but why make a German bow with a grip in the first place?

The bow I've been playing the most for years has no grip, though it clearly had one at some point before I got it- what might I expect if I were to have a grip added?