the space is in every aveo made. If they were still available new, I would tell you to go to a dealer and pop open every hood in the line of new aveos to see how it is supposed to look.

vw's have a floating suspension too. They have a slight space in them when installed too. Its when the gap "enlarges" or passes a certain distance, that they are worn. In the aveo it seems they are "acceptable" until almost 3/8" and a 1/2" requires definite replacement.

just the shear design, if you tighten the upper cap to the strut uninstalled, you will see a gap between the mount rubber and cap. The thickness of the strut tower metal is not enough to fill that. period.

look up "VW strut top gap" use google and search images. this will give you pictures, and clicking on them will take you (often) to discussions on the subject.. which will further explain it to you.