CARAVANNERS have welcomed a clampdown on thieving backpackers in a West Australian coastal town.

"These rogues are giving us all a bad name," Victorian grey nomad Horace Day, 72, told Caravanning News. "We are sick and tired of all us travellers being tarred with the same brush."

Mr Day's comments follow a police warning to overseas travellers that shoplifting would not be tolerated after 20 French tourists were charged with allegedly stealing from Woolworths and IGA stores in Carnarvon, 900km north of Perth.

According to reports, previous French tourists are using internet forums to encourage others to subsidise travel costs throughout Western Australia by theiving, and Carnarvon is just one location on the backpacking journey circuit.

Near destitute foreigners have claimed they are forced into stealing after heading north for the warmer weather only to find there was little or no work available to replenish their funds.

"Ill prepared, the backpackers are under-estimating the cost of travel and accommodation in Australia and the distances between locations," police said in a statement.

"They are sleeping in their vans or camping in bushland, purchasing or hiring vans for their Australian adventure that by the time they get to Carnarvon break down.

"They arrive in Carnarvon with little money in the hope of getting seasonal work after spending time in the South West of the state, getting occasional work when they can."

Police said there has been a significant amount of stealing offences committed in supermarkets by French backpackers in the Mid West-Gascoyne.

"In some cases they have consumed food items whilst walking through the store and then failed to declare the item.

"We want overseas visitors to understand this behaviour will not be tolerated."

Carnarvon Police have now posted signs in French and other languages at the local supermarkets advising that anyone caught stealing from stores would be arrested, prosecuted, could be jailed and have their visas cancelled.

Mr Day said he had seen newspaper reports of grey nomads being wrongly blamed for crime in some country towns.

"I'm glad the WA police have pinpointed overseas travellers as being the culprits in one of their holiday destinations ... I just wonder how many other shoplifting cases can be attributed to overseas visitors in other parts of Australia."

Queensland caravanner Rod Baxter, who has been on the road fulltime since retiring as a warehouseman, described how he often came across travellers camping in the bush and carparks.

"Many are over here on work visas but are having problems finding employment and are desperately short of cash. They live on two-minute noodles because it's all they can afford.

"Some have even told me how they frequent cafes and eat leftovers after other people have left their tables.

"Being a softie, I can't help but feel sorry for some of them and have lost count of the number of times I have shared my meals with them. Some are great company."