The government on Sunday warned it would delist hotel operators from its latest tourism stimulus campaign known as Rao Tiew Duay Kan (We Travel Together) if they are found to have increased their room rates.
The latest effort to bolster the economy subsidises 5 million nights of hotel accommodation. Tourists are meant to pay only 60% of normal room rates, with the government responsible for the other 40%, and the subsidy capped at 3,000 baht per night for up to five nights.
More than 3.6 million people have signed up for the package since online registration began on Wednesday, said deputy government spokeswoman Traisuree Taisaranakul on Sunday.
However, she also warned all hotels joining the programme not to increase their room rates to take advantage of the 40% subsidy from the government. Some netizens say the price-gouging among opportunistic hotels has already begun.
"Any hotels caught price gouging will be scrapped from the programme immediately,'' Ms Traisuree said.
The government warning came after several registrants complained of inflated room rates on social media.
One person wrote on a Facebook page that a hotel she planned to stay at had advertised a rate of 2,200 baht per night, but the amount increased when she tried to register with the tourism promotion campaign.
The rate was now 4,000 baht per night, or 2,400 after the 40% discount rate, she wrote without naming the hotel.
Another person also wrote on his Twitter account: "It's more expensive now when you try to register with the tourism promotion campaign. Same day, same room, but different prices. How's this possible?"
He posted a photo showing the prices of his booked hotel room has gone up from 7,546 baht for two nights to 11,196 baht after registering with the tourism promotion campaign.
"This stimulus campaign aims to boost the domestic economy and help the hospitality and service industry, so we hope hotel operators will not take advantage of their guests during this difficult time," Ms Traisuree said.
She said most of the registrants had reserved one-night stays in hotels in eastern and western provinces with Krabi being the most popular long-distance destination.
"So far, the registration process has gone smoothly," she said.
"There was a minor problem with delays on receiving a one-time password to enter for the registration process, but only a handful of people experienced this issue."
Ms Traisuree said the scheme is expected to have more registrants this week as there will be a long weekend from July 25-28.
Udom Srimaha-chota, vice-president of the Thai Hotels Association, also urged hotel operators nationwide to not take advantage of the 40% subsidy.
"We've informed our members about the punishment for price gouging. Most hotels understand the rules and are willing to cooperate. However there might be some bad operators," Mr Udom said. "If they are caught, they will be delisted from the campaign and must return all the money received from the government."