I got mine from fourparks also. On the shipping information, it said signature required. But they may sometimes be a little lax about actually requiring that when it's USPS (UPS is usually stricter).
It is a bit aggravating to have to sign for it, but it's a smart thing for a seller to do. There is so much fraud on eBay, especially in the buying and selling of handbags. Sadly, there are people who would claim it never got there and demand to be refunded and keep both the bag and the money. The only defense a seller has is to have proof that the bag was actually delivered.
Also, for sellers on eBay selling "high risk" items like handbags, they may have their money held by PayPal for 21 days unless the buyer leaves positive feedback or until delivery can be confirmed. Again, a good reason for requiring a signature.