Good play, bad play or misclick?

[bkm]

$10+1 Party Poker No-Limit Hold'em Tourney, Big Blind is t200 (4 handed) converter

Button (t1434)
Hero (t930)
BB (t4596)
UTG (t1040)

Preflop: Hero is SB with 7[img]/images/graemlins/club.gif[/img], Q[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">2 folds</font>, <font color="#CC3333">Hero raises to t930 (All-In)</font>, BB calls t730.

Flop: (t1860) 6[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players, 1 all-in)</font>

Turn: (t1860) J[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players, 1 all-in)</font>

River: (t1860) 3[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players, 1 all-in)</font>

Final Pot: t1860

Hero has 7c Qd (high card, king).
BB has 2c 3s (one pair, threes).
Outcome: BB wins t1860.


The BB has been playing a good game and has used her big stack well. So, why does she call my all-in with a hand that, at best, is only going to win 1 in 3 times?

If she folds, she has more than half the chips with the rest of the chips pretty much evenly divided between the other 3 players. While we're playing conservatively, waiting for each other to bust out, she could use her big stack to wear us down.

Am I missing anything here?