200/400 Durrr vs PA

[ArmenH]

Why did PA(Dampest Hawk) bet river here? I don't understand this hand he can win showdown but gets called by any A. This didn't make sense to me what do you guys think? Is a naked Ace supposed to check fold river here?

Full Tilt Poker Game #1777066873: Table Canfield (6 max) - $200/$400 - No Limit Hold'em - 17:05:39 ET - 2007/02/11
Seat 1: pareshjain ($43,000)
Seat 3: durrrr ($48,448.50)
Seat 5: TerrorOfSweden ($16,000)
Seat 6: Dampest_Hawk ($51,798)
durrrr posts the small blind of $200
TerrorOfSweden posts the big blind of $400
The button is in seat #1
*** HOLE CARDS ***
Dampest_Hawk raises to $800
pareshjain calls $800
durrrr calls $600
TerrorOfSweden folds
*** FLOP *** [Ad 2h Ah]
durrrr checks
Dampest_Hawk checks
pareshjain checks
*** TURN *** [Ad 2h Ah] [Jd]
durrrr checks
Dampest_Hawk checks
pareshjain bets $700
durrrr raises to $3,750
Dampest_Hawk raises to $9,600
pareshjain folds
durrrr calls $5,850
*** RIVER *** [Ad 2h Ah Jd] [8c]
durrrr checks
Dampest_Hawk bets $22,700
durrrr has 15 seconds left to act
durrrr calls $22,700
*** SHOW DOWN ***
Dampest_Hawk shows [Js Ts] (two pair, Aces and Jacks)
durrrr shows [5c Ac] (three of a kind, Aces)
durrrr wins the pot ($68,098) with three of a kind, Aces
*** SUMMARY ***
Total pot $68,100 | Rake $2
Board: [Ad 2h Ah Jd 8c]
Seat 1: pareshjain (button) folded on the Turn
Seat 3: durrrr (small blind) showed [5c Ac] and won ($68,098) with three of a kind, Aces
Seat 5: TerrorOfSweden (big blind) folded before the Flop
Seat 6: Dampest_Hawk showed [Js Ts] and lost with two pair, Aces and Jacks