is encouraging people to get together with friends and flags up mid-week discounted entry prices.
"Do you know a friend in need of a great day out -- away from work? Simply email this URL ihatework.co.uk to them and they can get out of the office and have a great day out at Alton Towers," the site says.
The Federation for Small Businesses said that the website was unethical and that it encouraged absenteeism and should be taken down.
Stephen Alambritis, FSB head of parliamentary affairs, said: "Every company has the right to market their products as they see fit and discount their products and services as required. But the website I Hate Work is unethical and should be taken down. We are hopeful that Alton Towers will see sense."
He added that if Alton Towers did not take the site down the FSB would investigate other avenues such as a complaint to the Advertising Standards Authority.
Alton Towers, however, is refusing to backdown. A spokeswoman for the amusement park said there are no plans to take the site down.
"Two thousand vouchers have already been downloaded from the site. The campaign is not intended to encourage people to skive, we are encouraging people to consider taking legitimate time off during the week to take advantage of chaper entrance and shorter queues," she said.
The site has been launched on the back of research that reveals more than a third of the park's adult visitors were on unofficial leave with male skivers outnumbering their female counterparts by two to one. It found that the biggest culprits were visitors from the North -- 60% of those admitting they were skiving -- against a third of Southerners.
Alton Towers said its skivers claimed they were throwing sickies because they did not get enough holiday time.
Mike Lorimer, marketing manager at Alton Towers, said: "We were actually quite surprised by the number of skivers we appear to have on park, and expect our Ihatework.co.uk website to be really popular as a result."
He added: "It's not up to us to reduce absenteeism and if workers want to take advantage of the mid-week deals, why not?"
The FSB estimates that absenteeism is a major problem for the nation's businesses and costs the UK economy 拢10bn each year.
"Staff 'pulling sickies' is demoralising for other employees. It is also a disciplinary offence. How would management at Alton Towers like it if their staff pulled a sickie to spend the day at Chessington World of Adventure or Blackpool?" Alambritis said.
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