Treasurer Joe Hockey is sticking by his comments that rich people spend more on petrol.

Joe Hockey is sticking by his comments that rich people spend more on fuel than poor households.

The government wants to reintroduce twice-yearly indexation of the fuel excise, a budget measure opposed by both Labor and the Greens who say it will hit low-income families the hardest.

But the treasurer disagrees, saying there there was a clear trend that showed the higher the household income, the more fuel taxes were paid.

"The poorest people either don't have cars or actually don't drive very far in many cases," he told ABC Radio in Brisbane on Wednesday.

That comment drew a rebuke from Labor leader Bill Shorten and some welfare groups.

"Are you serious, Joe Hockey? Are you really the cigar chomping, Foghorn Leghorn of Australian politics where you're saying that poor people don't drive cars?" Mr Shorten told reporters in Perth.

St Vincent de Paul Society chief executive John Falzon said the treasurer was making a massive assumption.

"In fact many low-income households are heavily dependent on quite old motor vehicles that are not terribly fuel efficient as their only means of transport," he told Fairfax Media.

Cheaper housing was also often located in areas that were poorly served by transport, but far from jobs, so they have to travel long distances at times.

When quizzed by reporters in Perth later on Wednesday, Mr Hockey was unrepentant, labelling the reaction to his comments as "hysteria".

"The fact is that there is a clear trend in Australia - the higher the household income the more fuel taxes are paid by the household," he said.

His office also released figures that showed average weekly expenditure on petrol ranges from $16.36 for those on the lowest income to $53.87 among the highest incomes.

Households in relatively disadvantaged areas were also less likely to own motor vehicles than those in relatively advantaged areas.

Where motor vehicles were owned, households in relatively disadvantaged areas were most likely to own only one car whereas households in relatively advantaged areas were more likely to have two or more motor vehicles.