Plus size clothes that are just larger cuts of the exact same pattern for smaller clothes, so if a shirt is 1" wider then it's also somehow 1" longer. How many adults grow taller as they grow fatter? It completely changes the look of the item.
Imagine if they took plus size clothes built for bigger bodies, bigger bellies and boobs and then just sized them down for smaller sizes. The fit would be ridiculous. I feel like fat people deserve to have well fitting clothes like smaller people do.