I used to order from them quite a bit, bought 3 great Schon's from them, always had big orders, so shipping was cheap or free. Always liked them.
After reading this I put a hat in my cart and checked shipping. $23. While cheaper than your quote, still really high. As it was about $13 cheaper, I wonder if what is going on is when you order, Seyberts isn't the one that is shipping. That would explain the difference in what I saw and what you were quoted as the hats are actually being shipped from the producer.
Just for kicks, put a different brand hat in your cart and see if you get a different ship rate.
Edit I just read Slides post and he got a different rate yet.