And furthermore the OP bought it in December in Minnesota and just took delivery of it.
If one is picky about rust one should try to prevent it. The OP mentions the cutter sat outside over the winter, maybe he should have gotten it inside.
TBN has seen many complaints about stuff weathering at the dealers, it's a "fact of life". Perhaps there are dealers with acres of indoor storage in a climate controlled environment but I have not seen them and I would expect their prices to be higher. All dealers I've gone to visit have "new" equipment sitting outside with slight weathering.
If I wanted something in "pristine" condition I would expect to pay a little more and move it to my environmentally controlled area so I could keep it in "pristine" condition. I've gotten in the habit of walking around my "stuff" with a spray can of Fluid film just so I can spray stuff (bought a case for about $7/can on ebay). I dislike rust. I dislike growing old. But what's the alternative?
And I trust in dealers and mother nature. They have to store implements outside to have good prices and mother nature has to put iron and oxygen together in the presence of moisture.
All of my 3pt equipment gets used and is subjected to getting scratched by rocks, dirt and branches. I don't know how much it would cost to ensure the metal never became exposed but I'm sure it would be a lot. And I sand and scrape stuff and repaint occasionally. I think a paint coating that would ensure my plow never rusted would be very expensive.
Perhaps TBN needs a FAQ that includes things like - "when you buy something check it over BEFORE you buy it", "rust happens", "if you don't like the mud keep off the ground"