Why does aluminum have a shiny and a matte side?

In some states of mind the question is more interesting then the answer:

Wiki says:

"Aluminium foil has a shiny side and a matte side. The shiny side is produced when the aluminium is rolled during the final pass. It is nearly impossible to produce rollers with a gap fine enough to cope with the foil gauge, therefore, for the final pass, two sheets are rolled at the same time, doubling the thickness of the gauge at entry to the rollers. When the sheets are later separated, the inside surface is dull, and the outside surface is shiny. This difference in the finish has led to the perception that favouring a side has an effect when cooking. While many believe that the shiny side's reflective properties keep heat out when wrapped on the exterior and keep heat in when facing exterior, the actual difference is imperceptible without instrumentation ^[7]. Thereflectivity of bright aluminium foil is 88% while dull embossed foil is about 80% ^[4]."

Here is a How It's Made for aluminum foil, they don't explain the two sides though: