That's rather disappointing since its unlikely you'll get them out without destroying at least two of the four
I've often wondered whether that tiny difference is really that important or whether its just engineers nerding out a bit. The two joints do move differently though - the outer hub joint primarily rotates in a single axis along the joint. The wishbone joint rotates along its axis, but also in an arc perpendicular to its axis - you can see it if you move the wishbone up and down with the bolts loose. I think this arc is the reason for having less rubber in those inner bushes, so they can twist in a second axis.
From an engineering standpoint, having the all-rubber bushes in there would mean less compliance in the bush therefore it would increase the load on the aluminium housing in to which it is pressed. Whether or not that increased load would have any measurable impact is purely conjecture until someone tests it!