Webber has left F1 after 13 years in the world championship to race for Porsche in the World Endurance Championship and Le Mans 24 Hours from this season.
Although his compatriot Daniel Ricciardo has taken his place alongside Sebastian Vettel at Red Bull, Webber fears opportunities are diminishing for drives from the Antipodes to follow in their footsteps.
"You still need to get to Europe pretty early. I've always said that I would like to have done some European karting earlier," said Webber, who is guiding the career of New Zealand's Mitch Evans, the 2012 GP3 champion.
"But it's just so expensive now to get out of Australia and to prove yourself. It's always been tough, but now it's very, very difficult, as we're finding with Mitch and those guys.
"With Kiwis and Aussies, it's just hard to penetrate through. We don't have the numbers in our country.
"Back in my day when it was Marlboro [funding young drivers], you didn't sell many cigarettes in Australia but you sell a lot of cigarettes in Brazil.
"And Russia now, there's a lot of people there and that can help [driver funding]."
Webber first came to European racing to compete in British Formula Ford in 1996. He then reached F1 via British Formula 3, a stint in Mercedes' factory sportscar team, and Formula 3000.
He admitted that the growth of Australia's V8 Supercars series gave young drivers an incentive to build a career in their homeland rather than aiming for F1.
"There's a lot of talent in Australia, no question about it, but there's a very good domestic series with the touring cars, and guys sometimes realise that's an option for them instead of coming to Europe," said Webber.
Although Webber has been critical of how important personal sponsorship has become in the F1 driver market, he highlighted McLaren's choice of Kevin Magnussen for 2014 as a cause for optimism.
"It's refreshing to see someone like Kevin getting a run, that's great," he said.