Nuck, and I've seen the claim that VG is more sticky than G.
Yes, vegetable glycerin is derived from vegetable fats, and glycerin/glycerol without the "vegetable" in it's name may be derived from animal fats. That's why I acknowledged that they may have a different route to the sales shelf in my post. But the bottom line is this: The resulting chemical compound, no matter what it is called, is C3H5(OH)3.
Could it be that the 1% or up to 5% impurity makes enough of a difference for people to detect a difference between brands? I don't know. But I do know that if the chemical compund is the same, what you got is the same. So unless someone is a vegan, or has other similar reasons to avoid anything made from animal fat, there is no difference, for ecig purposes, between vegetable glycerin, glycerin, glycerine, or glycerol.