Sometimes machine cutting tools leave carbon residue that can seep rust, but sand and salty dust can also deposit rust-able elements on stainless products. Thus leaving a rusty look. Hard to say, but in any case, oil with something like break free or WD-40 would help.
If the metals are simply wrong. We need to know, so give any defective one back to your dealer to return to us for inspection. We need to know if our vendors have changed something. Try a magnet on the part to check for proper stainless steel elements... they should not react to the magnet... very much.
Director of Parts and Accessory Sales
Hobie Cat USA