Adidas Group own the Adidas brandmark, and they license it to anyone willing to pay enough. Seeing "Adidas" on an item is not an indication that the thing was made by Adidas, designed by Adidas or has anything to do with Adidas beyond a fee to use the logo.

You need to really dig in to the background of where something comes from to understand what you're actually paying for. This is why paying more for brand name goods is often a bit silly.