Pretty much this, and that's why they have the general 'cobbled look' too if you ever get really close and can see rivets and such just wherever (to the layperson). I didn't figure this out until I was in college, growing up I always figured it was cost saving or superstition.

So, if you want to make random country look weak and like they're flying clunkers, all you have to do is zoom up closer in to the craft and for an added bonus yellow filter of poverty.