Your still not getting this. You can not register the product for warrenty or take any other action as if you bought this from a legit store. As long as pioneer does not sell to the vendor, then they do not and will not give the final buyer any warrenty what so ever or for any reason. It doesn't matter if you register via warrenty card or even the internet. If you ever send Pioneer that product for repair they will send it directly back to you as if you sent them an alpine head unit.
When you buy most any audio product via un certified channels, you get no warrenty other then from who you are buying the product from. It says right on there warrenty that you must purchase from an authorized dealer to get a warrenty.
Many times the product you buy through these channels are actualy B-Stock or refurbs or resold products via employee discount programs.
Just read JL audios disclaimer. The only diverence is that JL puts it up front on there site and pioneer still hides it on their warrenty documentation
http://mobile.jlaudio.com/jlaudio_pages.php?page_id=111.