Representatives for hoteliers have dismissed charges of "price-gouging" and insisted to an Oireachtas committee that rates in Dublin are competitive.
But members of the Tourism Committee pointed to prices of €800 a room, and demanded immediate action to bring these "exorbitant" costs down.
Eoghan O'Mara Walsh, Chief Executive Officer of the Irish Tourism Industry Confederation, said that the average room cost €154 in April, up 16% on 2019.
The "significant jump" was due to inflation, pent-up demand and a lack of supply, he said, and he expects figures for May to reveal a further 16% rise.
But he warned that "2023 is going to be far tougher, far softer" for hoteliers, and appealed for continued Government support, warning that the sector won't see a full recovery until 2026.
Earlier in the Dáil, Sinn Féin's Pearse Doherty said that sports fans heading to Croke Park for the All-Ireland quarter-finals this weekend face "rip-off prices".
These include "€167 for the pleasure of sleeping in a bunk-bed with nine other strangers in the dorm," Mr Doherty said.
Fianna Fáil Senator Shane Cassells condemned the "exploitation" of sports fans as "fundamentally wrong."
And he asked Government officials attending the committee if the lower VAT rate the tourism sector benefits from should be allowed to continue regardless.
The Government's view, Bernard O'Shea from the Department of Culture replied, is that "all matters would be on the table" when considering any extension to the lower rate.
Mr O'Mara Walsh agreed that the price Senator Cassells was quoted - almost €800 for a room - was "excessive."
It appeared that "Dublin is full", he said, adding that better value would be available at other times.
The committee heard that the capital has just over 18,530 hotel beds available, out of a stock of 22,492.
The remainder are either out of use, or are tied to long-term contracts.
Paul Kelly, CEO of Fáilte Ireland, said he is "most worried" about the high cost of car rental, an issue raised by Fine Gael Deputy Brendan Griffin.
Mr Kelly revealed that he has told the Government that the way Value Added Tax and Vehicle Registration Tax costs are administered are contributing to this, and warned that unless action is taken it "will damage tourism in Ireland on an ongoing basis".
Dublin city has the highest occupancy rate in Europe at 83.6%, Tim Fenn, CEO of the Irish Hotels Federation, said, adding that the city saw a faster rebound post-pandemic than anyone anticipated.
Imelda Munster, Sinn Féin TD, suggested that Mr Fenn would "look quite silly" if he refused to acknowledge that "price-gouging" was taking place.
"Where was that VAT rate reduction passed onto customers?", she asked, quoting rates which were multiples of those offered in other European cities.
Mr Fenn insisted that room rates are competitive when the average price is looked at, rather than "these rates that the committee seems to be focused on."
High rates charged for "last available rooms" conceal the "significant value out there," he maintained.
But Fine Gael Senator Micheál Carrigy pointed out that the cheapest hotel room he could get in April was €600, "and that wasn't last minute."
"I think the hotel industry has to give something back to the tax-payer," the senator said.
"Hotels are big users of energy", Mr Fenn said, noting that the industry was grappling with surging prices.
Denyse Campbell, President of the Irish Hotels Federation, spoke to one hotelier in the south whose energy bill in March was €14,000.
In April, it tripled, rising to €42,000, she said.
Ms Campbell insisted that the VAT rate for hotels should not be increased in the wake of criticism of the high prices being charged for rooms.
Speaking to RTÉ's Drivetime, she said: "I think the 9% VAT rate really is the correct rate for the long term sustainable growth of our industry and it would be a shame if people were to discuss the VAT rate in this context because I do feel that this year is an anomaly.
"2022 is a year like no other and really 2023 will be a totally different year for us, and we do need the battery to be at 9% because if it goes back up to 13.5% we won't be competitive."
She said that there are a number of factors at play that have led to elevated prices.
"We've a lack of supply in the market. We've got pent up demand. We're dealing with the deferred business."