For those who have to work on Bank Holidays, there is a law to compensate them for missing out on the day off.
https://www.workplacerelations.ie/en/what_you_should_know/public-holidays/
When a person works on a public holiday they are entitled to be paid for the day in accordance with their agreed rates. In addition, they also have an entitlement to benefit for the public holiday. This can be different for each public holiday and each employee depending on the individual's work pattern.
If the business is closed on the public holiday and an employee would normally be due to work, then they get their normal day's pay.
If the business is open and an employee works, he/she is entitled to either paid time off or an additional day's pay. The additional day's pay is what was paid for the normal daily hours last worked before the public holiday.
If an employee is not normally rostered to work, then they will be entitled to one-fifth of their normal weekly wage extra.