Couples told the Orange County Register that Zalatoris, now 26, turned down a $US130 million ($A195 million) offer to join the controversial rival to the PGA Tour.
"Money is zero object (for LIV Golf)," said Couples, who shares the same agent as Zalatoris. "I give Will a lot of credit; he wants (to stay) with the PGA Tour."
Like Couples, Zalatoris has been an outspoken critic of the new 54-hole league.
In the autumn, he said on "In Depth with Graham Bensinger" that "I've never done this for money. If the US Open had a $100,000 purse, I'd still show up to the US Open ... I'm in this to win a major. That's my career goal."
LIV Golf began its second season last month with 12 teams of four players apiece, featuring Phil Mickelson, Dustin Johnson, Bryson DeChambeau, Brooks Koepka, Bubba Watson, Spaniard Sergio Garcia and Australian Cameron Smith among their biggest names.
A former All-American at Wake Forest, Zalatoris is closing in on first career major - he was runner-up to Hideki Matsuyama at the 2021 Masters, then lost in a playoff to Justin Thomas at the 2022 PGA Championship and tied for second behind Matt Fitzpatrick at the 2022 US Open.
In just his third full season on the PGA Tour, Zalatoris has $US14.3 million ($A21.4 million) in career earnings after winning his first event last August at the FedEx St Jude Championship.
