Lots of Aces Sends One Out

We arrive to see John Bettencourt all in for his last 10,450 on a board of A♣4♦3♦ and he gets two callers.
The turn is 3♠ and both players check.
The 5♥ hits the river, one player checks and the other turns over A8 for two pair, but his kicker isn't good enough as the other shows AT.
Bettencourt mucks, grabs his Turlock Poker Room goodie bag and packs up for the day.