Is it possible that my new iPod touch is a used one? I've purchased a new iPod touch 4G last week through a 3rd party reseller. I saw the packaging is still good in white plastic around the acrylic box. The seller assured me that the product is new and still in sealed condition. 

Then, he unsealed the box to open it and picked the unit to another room (he said that he wanted to activate it first). 5 minutes later, I received the unit again and noticed that the iOS was 5.1.1 (I thought it was supposed to be 5.0.1 considering it was released in 2011)

Then I went home to register the iPod in my ASP (with the SN of course). However, after I put in the serial number, this came up :

According to our records, this serial number is registered to another Apple ID. If you have more than one Apple ID, log in to My Support Profile with that Apple ID to see your other registered products. Not sure if you have another Apple ID? 

As I was about to contact Apple with telephone support, this came up :

1. Valid purchase date

2. Telephone technical support : Expired

3. Repairs and Service Coverage : Active, 2 August 2013

4. Elgible for Apple Protection Plan 

Yep, the telephone support had expired and the warranty was less than 365 days. I went back to that guy for an explanation but he said that I'd better bring this matter to the Authorized Service Provider. Before I went there, I did noticed that the iPod touch often freeze after "slide to unlock" and I had to hard-reset it to get it back working. Then, it's battery capacity was awfully weak; I used it for music then it got 20% warning in just 2 hours from full charge.

So I did go the Authorized Service Provider, but the guy at the ASP laughed at me because I've received a quite non-functional product which was not supposed to be sold to customer just by looking at the serial number and the part number (ZP). Honestly, I don't even know where was ZP region located ? (My iPod touch 3rd Gen was a ZA actually). Those guys also said that Apple won't be held responsible for such thing.

Hence, I don't know where should I bring this matter, since both sides (reseller and ASP) are dead-end. I wanted to ask guys here if there were really such thing as "not supposed to be sold" iPod touch. Or if there's someone else have the same problem as I did.

I can only think of one thing, probably this iPod was a display unit, then somehow, the seller cleaned the box and the unit then resealed it again to make it looked new. I don't even know if it's possible to reseal an iPod packaging.

I don't know where else to ask, so I hope that I might find something here.
Phone AppleCare, they will have more details on the original purchase date, location and registration details. Then take this information to the reseller and demand your money back if it was sold as new. If they are an Apple Authorised Resealer consider reporting them to Apple for not following the correct sales procedures. 

In future I would suggest buying directly from Apple wherever possible.