Full Tilt $20 Multi Scenario

[Lucas McCain]

$20 buy in 40 mins into the tourneyment, I have 6200 chips 101 entered 64 remaining. Blinds are 40/80 I put it to 220 with KK in middle position and the SB raises to 650 comes back around to me and I put my whole stack into the pot. He sits for 5 seconds and calls 6200 with AJ off he has 440 more chips than me gets his Ace I am out. What is it that these guys are thinking when they call off this valuable a chip stack with this horrible a hand? I dont know......