The former boss of Britain's biggest bookies lobbied against betting machines he labelled the "crack cocaine of gambling".
Stewart Kenny, the founder of Paddy Power, urged the Irish government not to legalise the machines - which allow punters to place £100 every 20 seconds.
Mr Kenny, who left Paddy Power this summer, described fixed-odds terminals (FOTBs) as "dangerously addictive", The Times reported (£).
In his submission to the Irish government, Mr Kenny said disadvantaged people were particularly vulnerable, and urged the country not to follow the UK by legalising them.
Over the past year, bookmakers made £1.75 billion from FOTBs - raking in £438 million in tax for the UK government.
Arguing against the machines' licensing, Mr Kenny warned that the British government was "as addicted to the tax revenue [from the machines] as vulnerable customers are to losing money in them".
Anti-gambling campaigners have demanded the maximum stake on FOTBs be cut to £2 from £100.
Mr Kenny made his comments in a written submission in 2009.
Mr Kenny wrote: "Let us learn from the mistake in the UK of allowing them into betting offices, once they are in it is impossible to get rid of them or even curb their more addictive elements".
Ultimately, the Irish government opted against legalising the machines.