Four auto makers are the latest to announce they will not attend the Australian International Motor Show in Sydney this October.

Audi Australia Pty. Ltd., Aston Martin Lagonda Ltd., Rolls-Royce Motor Cars Ltd. and Land Rover say it costs them as much as A$2 million ($1.8 million) to exhibit at both the Sydney event and the Melbourne International Motor Show, held Feb. 29-March 10.

A number of auto makers have been pushing for one show to be held in Australia each year that would alternate between Melbourne and Sydney. The two cities are located 550 miles (881 km) apart.

But organizers of the two events appear unwilling to make the change.

The Victorian Automobile Chamber of Commerce, which runs the Melbourne show, was buoyed after this year’s event attracted 243,089 attendees – only the fifth time since the show began 74 years ago that attendance has exceeded 240,000. The Melbourne event is Australia’s longest-running auto show

The increased attendance, up 6% from last year, came despite a dozen major auto makers not exhibiting at the show.

Melbourne show director Russ Tyrie says the two shows complement each other.

“As always, diversity was the key, with many (Melbourne show) patrons coming to see the A$2.7 million ($2.4 million) Bugatti Veyron in the first three days,” he says. “But even more (came) to see the new (Ford) FG Falcon range and Holden’s Coupe 60, as well as the amazing self-parking Lexus demonstrations.”

The Federal Chamber of Automotive Industries, which organizes the Sydney event, insists this year’s show will go on.

Meanwhile, Audi, which favors one show a year, says it has quit exhibiting because it has been spending A$1million ($896,900) on each show.

“The cost of two major motor shows a year is crippling,” an Audi spokeswoman is quoted as saying.

“It’s unlikely we’ll be in Sydney. There’s not much press coverage coming out of the shows these days – the cars are being unveiled internationally beforehand or the lion’s share of publicity goes to local models.”

Mercedes Australia/Pacific Pty. Ltd. decided not to attend either show this year, while BMW AG and Porsche AG say they will not exhibit at the Sydney event.

In all, 13 auto makers so far have said they will not display at the Sydney show.