nl50 - standard river betfold on gross board?

[BadBigBabar]

nl50 online
villain is 22/4 over 400 hands, no specific reads

CO ($32.15)
Button ($36.60)
SB ($15.55)
Hero ($48.50)
UTG ($49.50)
UTG+1 ($46.20)
MP1 ($70.65)
MP2 ($52.70)
MP3 ($44.50)

Preflop: Hero is BB with 4[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/spade.gif[/img].
UTG+1 calls $0.50, <font color="#666666">4 folds</font>, Button calls $0.50, SB completes, Hero checks.

Flop: ($2) 6[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/spade.gif[/img], 5[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(5 players)</font>
SB checks, Hero checks, UTG checks, UTG+1 checks, <font color="#CC3333">Button bets $1.25</font>, SB folds, Hero calls $1.25, UTG calls $1.25, UTG+1 folds.

Turn: ($5.75) 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG checks, <font color="#CC3333">Button bets $2</font>, <font color="#CC3333">Hero raises to $6</font>, UTG folds, Button calls $4.

River: ($17.75) 7[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $11</font>, <font color="#CC3333">Button raises all in for 28.85</font>, Hero folds.

Final Pot: $37.75

i felt like he's basically never raising a chop or a worse hand. what do you guys think? do you play the flop differently?