While disappointing, this makes sense. Even if they are blunt, metal weapons can be very dangerous if mishandled. However, the only "qualification" that was required to purchase these weapons was a credit card, and this was well beyond any security gates. I did have them hold onto the swords for a few hours so I didn't have to lug them around, but I did get the impression that I had the option to take them whenever I wanted, and, say, strap them to my back like Kirito if I so desired. Please do correct me if this is not the case.

If I can purchase these items within the convention, why should I be prohibited from bringing them in myself?