Why do osprey have beaks?

Avocets often feed by wading, head pointed downward, in shallow water, waving their heads (with bills partly open) from side to side. Small creatures are snapped up, or get caught in the filtering membranes within the bill. Having an upward curving bill lets the end of it be parallel to the ground when the bird is doing this. That way more area can be swept with each pass. A hockey stick is bent the same way for the same reason. The bill tapers to a fine point, too, to reduce drag in the mud. Hockey sticks don't need that adaptation.