Your definitely incorrect about quite a few things again. The matte display is the bare LCD panel. Then the glossy does have a bezel; I have seen videos of the glass being removed. And the black border around the display is either plastic glued to the glass or a dyed/painted area of the glass, because the LCD panel is rectangular and does not extend to the edges of the lid. I am a little surprised you think this as well. And I think the older iPhones and iPod touches use a type of plexiglas as well. I have not seen an iPad and the iPhone 4 is made with gorilla glass.
It really seems from your comments that you are making quite a few assumptions based on no real information. Furthermore you sound like you have never seen a LCD panel outside of it's frame. Well I will give you a clue, they are all rectangular and have ninety degree corners. Then there is no way apple would use resources to made LCD panel extend from edge to edge then just disable a percentage of the display around the border. LCD panels are becoming cheaper, but it should be obvious why this would not be economically sound versus using a plastic bezel or dying/painting the edge of the glass cover.
Finally if you have ever seen the "glass" on the MacBook pro break, it does not shatter like glass but rather cracks and splits like an acrylic.
Plexiglas
http://en.m.wikipedia.org/wiki/Poly(methyl_methacrylate)?wasRedirected=true