Why does no one use Stainless Steel? It weighs the same, can't see a noticeable difference in price?

The 2mm stuff I had on BitzaWood stood up pretty well. LH's punch axe head put holes in it, but everything else just scuffed it. It was only really 360 that put it massively out of shape, and even blew holes in it! But we all know what 360 can do.