Interesting Play

I was watchin $15/$30 at Full Contact Poker, when I saw the following hand occur:

Texas Hold'em $15-$30

Seat 1: Player 1 ($1,182.95 in chips)
Seat 2: Player 2($138 in chips)
Seat 3: Player 3 Player 3($1,000 in chips)
Seat 4: Player 4 Player 4($1,531 in chips)
Seat 5: Player 5($264.50 in chips)
Seat 6: Player 6($1,126.90 in chips)
Seat 7: Player 7($4,715 in chips)
Seat 8: Player 8($754.50 in chips)
Seat 9: Player9($600 in chips)
Seat 10: Player 10($634.25 in chips)

Player 2 posts blind ($7.50), Player 3 posts blind ($15), Player 9 posts blind ($15).

PRE-FLOP:
Player 4 calls $15,
Player 5 raises $30,
Player 6 calls $30,
Player 7 folds, Player 8 folds,
Player 9 calls $15,
Player 10 folds,
Player 1 raises $45,
Player 2 calls $37.50,
Player 3 calls $30,
Player 4 raises $45,
Player 5 calls $30, Player 6 calls $30, Player 9 folds,
Player 1 calls $15, Player 2 calls $15, Player 3 calls $15.

FLOP [board cards JC,5H,3D ]
Player 2 checks, Player 3 checks, Player 4 bets $15, Player 5 calls $15, Player 6 calls $15, Player 1 calls $15, Player 2 calls $15, Player 3 calls $15.

TURN [board cards JC,5H,3D,3C ]
Player 2 checks, Player 3 checks, Player 4 bets $30, Player 5 calls $30, Player 6 folds, Player 1 folds, Player 2 calls $30, Player 3 calls $30.

RIVER [board cards JC,5H,3D,3C,10S ]
Player 2 checks, Player 3 checks, Player 4 checks, Player 5 checks.

SHOWDOWN:
Player 2 shows [ 7D,5D ]
Player 3 mucks cards [ AC,4C ]
Player 4 shows [ JS,KD ]
Player 5 mucks cards [ KC,AD ]

Player 4 wins $597.

Holy $hit. Unbelievable. What in the heck are you doing in that hand preflop with a 75sooooted and an A4sooooooted. And why in the heck does the A4sooooted think is gonna happen? Is he gonna hit his gutshot? Wing and a prayer. I need to play $15/30 apparently. WOW.