AQs ~ 3b pot, facing triple B

PokerStars - $0.10 NL FAST (6 max) - Holdem - 6 players
Hand converted by PokerTracker 4

BTN: $6.18 (VPIP: 66.67, PFR: 0.00, 3Bet Preflop: 0.00, Hands: 3)
SB: $22.40 (VPIP: 25.37, PFR: 17.91, 3Bet Preflop: 12.00, Hands: 67)
BB: $10.00 (VPIP: 15.38, PFR: 13.19, 3Bet Preflop: 5.56, Hands: 94)
UTG: $14.47 (VPIP: 22.01, PFR: 14.47, 3Bet Preflop: 13.11, Hands: 160)
Hero (MP): $12.52
CO: $10.00 (VPIP: 21.23, PFR: 18.06, 3Bet Preflop: 8.70, Hands: 558)

SB posts SB $0.05, BB posts BB $0.10

Pre Flop: (pot: $0.15) Hero has A♠ Q♠

fold, Hero raises to $0.30, fold, fold, SB raises to $1.20, fold, Hero calls $0.90

Flop: ($2.50, 2 players) J♥ A♦ 9♦
SB bets $0.78, Hero calls $0.78

Turn: ($4.06, 2 players) 3♠
SB bets $1.28, Hero calls $1.28

River: ($6.62, 2 players) 4♣
SB bets $3.30, Hero calls $3.30

Felt like it seemed odd he would bet that with AK and if he hit 2 pair prior to the river he would of surely bet bigger for protection. Thoughts?