Lyophilization Advantage
I don't think the point of freeze drying is to avoid liquid water -- I mean, there's liquid water already in the substance to be dried -- but to avoid heat.  Ordinarily, to dry something out to preserve it, you need to heat it to speed up the evaporation of water, certainly if you want to get rid of the water quickly (which you would want to do in any commercial setting, where time = money).  But heating causes all kinds of changes to foods, and while some foods are fine with it, others  suffer degradations of perceived quality, e.g. undesirable changes in color and texture.   The point of freeze-drying is that you can get rid of the water at a low temperature.