A key recommendation of the independent liquor review - to keep the Sunday closing time for hotels, taverns and small bars at 10pm - could be challenged by the Liberal Party, with some MPs declaring it an anachronism that no longer fits modern WA society.
The push for later Sunday hours also received the qualified backing of two key Labor MPs - shadow liquor minister Mick Murray and shadow tourism minister Paul Papalia - though both stressed it was a personal and not a party view.
But the recommendation to introduce secondary supply laws, which would create an offence for supplying alcohol to juveniles without parents' permission, received broad, cross-party support and appears certain to eventually become law.
The last major stocktake of the Liquor Control Act before yesterday's review, the 2005 Freemantle review, recommended extending Sunday closing to midnight but this was rejected by the former Labor government.
It preferred closing times on Sundays to remain at 10pm, with later closing to be dealt with by applications for extension permits.
This review, chaired by businessman John Atkins, recommends the status quo on Sundays but for a minor amendment that would allow pubs to close at midnight where a public holiday Monday falls on the following day.
Liberal MLA John McGrath said he favoured the extension of Sunday hours to midnight.
"I want to see it debated in the party room and I do believe a lot of Government members support more flexibility in trading hours," he said.
Mr McGrath was backed by North Metropolitan MLC Peter Katsambanis, who questioned why Sunday was any different to the other days.
"We are not here to push an industry barrow, we are here to look at the best interests of WA," Mr Katsambanis said.
"I think 10 o'clock closing on a Sunday sends an anachronistic message, especially to people who might have come into town on a Sunday ready to do business on a Monday."
Another Liberal MLA, Peter Abetz, disagreed.
"People have got Friday night and Saturday night to go out at the moment," he said. "I don't think we need another night out because of all the social problems that brings."
Mr Murray, who stressed the issue had not been considered by Labor's caucus, said WA had a seven-days-a-week economy.
"We don't all work Monday to Friday any more," he said. "For some people, Sunday night is their Friday night."
Liquor Minister Terry Waldron has said he would not comment on specific recommendations until he had further consultation with stakeholders.