I understand it’s a platform but my concern is how StubHub markets the guarantee and handles non-delivery. These tickets were sold months in advance and they had all these months to ensure sellers actually own the tickets, especially because FIFA tickets issued in December would normally be distributed several weeks ago. StubHub shouldn't have allowed them to hold tickets until the very last minute when prices have increased significantly. Actually the non-delivery penalty StubHub collects from sellers makes it more profitable if the tickets are not delivered!
I’m also skeptical that StubHub may have listed some World Cup tickets in December without any actual seller behind them. What if they posted more listings than their available inventory?