Order of magnitude cheaper to start with flat sheet, lasercut/waterjet/stamp out final shape, and bend. They are starting the cut and bend operations with the

Order of magnitude cheaper to start with flat sheet, lasercut/waterjet/stamp out final shape, and bend. They are starting the cut and bend operations with the fully hardened steel, so there is no post stress relieving / aging / finishing. It's about as simple as it can get for metal fabrication. Welding also fundamentally changes the underlying steel properties. I'm not up to speed on full hard 301 SS, but most likely any thermal operation will degrade it's mechanical and chemical grain structure.