Sawyer was having a bad time that moment, and to lift up his mood he agreed to go to NY with the given ticket for the sake of the person who couldn't go instead.
What's more, Sawyer was even determined to actually get the stuff shoved in his hands to be signed by Kishi as per request. He tried his best to do so, since he got there because of other people's charity. The least he could do to repay back was to get that freakin' sign, and he didn't do it for himself anyway, he didn't even think about it since he was aware that he wasn't as enthuthiastic as other fans regardless his own interest in Naruto series.
So for me, somehow, I feel bad for Sawyer at that time for being kicked out, but I could understand why of course. It's just... Whatever it is, good for him. Kishi is still an admirable mangaka, thus getting a chance meeting him in person is awesome enough.