Western Australia's footy fans are fuming over the cost of flights to travel interstate for AFL finals - especially Dockers fans who paid dearly to see their team lose.

They claim airlines are taking advantage of their loyalty and passion to turn a profit.

Fremantle supporters who flew to Adelaide for yesterday's qualifying final showdown with the Crows paid up to $1600 for a return ticket.

Perth people could have made the same trip last weekend for just $450.

While the purple army still made their presence felt at AAMI Stadium, it appears many more Dockers supporters would have attended the match if not for the cost.

Flight Centre in Fremantle said many shocked fans decided against going after being told of the huge cost.

Dockers banner team leader Maria Giglia said airlines were using fans' passion to make money.

"They're definitely taking advantage of us," she said.

"A lot of people can't afford it -- that's a lot of money. It's very sad, but what can you do?"

Both Qantas and Virgin Blue denied they were cashing in on the AFL finals series.

The airlines said because of the huge demand for flights to Adelaide the cheapest seats had sold out quickly, leaving fans to buy the remainder at higher prices.

Qantas put on two extra flights to help cater for demand.

"We're not taking advantage of anyone," a Qantas spokesman said. "It's purely to do with demand. We don't charge a premium for putting these special services on."

Virgin Blue spokeswoman Amanda Bolger said: "The seats are revenue managed, like all airlines, so as the aircraft fills up, the airfares increase."

A spokeswoman for the Australian Competition and Consumer Commission said it had not received any complaints about footy flights.

There was nothing it could do anyway, she said.

"We don't have the power in Australia to set the prices for any particular good or service," she said.

"The market will bear what the market will pay."

The Fremantle Dockers said many fans who could not afford the flights still made it to Adelaide by either car-pooling or taking the train.

A Dockers spokeswoman said other fans had probably decided against the trip in the hope of instead going to Melbourne in three weeks' time to see Fremantle in the Grand Final.

Ms Giglia said that despite the price barrier, many fans were still desperate to "be a part of history" yesterday.

"These are the sacrifices that you make," she said.

"It's our first away final ever. There's about 10 of us in the banner team who have gone over -- some have driven, some have gone by train and some by plane."

Despite the expense of getting to the match, local Docker fans were overjoyed about their team flying east.

Rob Carnemolla moved from East Fremantle to South Australia with his family when he was just 18 months old, but he never severed his ties.

Yesterday he was proudly wearing the purple scarf with his sister Jo.

"I used to go for West Coast, but when the Dockers started there was no other choice," he said.

"You get a bit of stick, but who cares. It's all good fun... until we play each other."

Adelaide Dockers fan Damien Pearce was more blunt about his reason for flying the Dockers flag.

"When I lived in WA, I developed a strong hatred for the Eagles," he said.

"Over here they are either bogan Crows supporters or bogan Port supporters.

"I might get 30,000 dirty looks from the bogans here today, but I got one high five from another Freo fan so that made it worthwhile."

Another SA Dockers fan, Glenn Roebuck, began supporting the team when he lived in Dampier.

"There's no other choice is there? This is huge," he said. (Australian dollar is the currency used in this report)