The musical band attached to An Garda Siochana cost taxpayers more than €1.8m last year.
Comprising 29 full-time musicians who have garda ranks such as sergeant and inspector, the troupe is not involved in policing duties.
They were paid an average of €60,000 each last year, and racked up travel and subsistence expenses of nearly €52,000.
The spending is likely to come under increased scrutiny after it emerged the band's counterpart representing the Irish Prison Service (IPS) cost just €2,500 to run this year.
IPS Pipe Band members are serving and retired frontline prison staff, who participate in musical activities on a voluntary basis during their time off, and pay for the cost of travel and accommodation themselves.
The group received just €2,500 of taxpayers' money this year, toward the cost of new drums.
A uniform is also provided by the prison service.
It performs at IPS events such as official openings, as well as a wide range of external engagements.
In 2018, the band performed at the National Concert Hall in September, in the Leeds St Patrick's Day parade in March, and at the Mater Hospital earlier this month for the lighting of the Christmas tree.
Similarly, the Garda Band provides music for official functions, as well as playing at events such as the Rose of Tralee Festival, the National Ploughing Championships and the Dublin St Patrick's Day parade.
In addition to salaries and travel expenses, €11,726 was also spent on communications and other equipment for the Garda Band last year, while training, development and incidental expenses amounted to €5,540.
Station services and maintenance of the band's own premises in the Phoenix Park cost €3,228. Almost €80,000 was spent on clothing and accessories for band members in 2016.
The Garda Band has cost taxpayers a total of nearly €7.3m over the past four years, according to figures released under the Freedom of Information Act.
In September, Garda Commissioner Drew Harris announced that overtime and other forms of discretionary spending would have to be cut for the remainder of 2018 due to budgetary constraints.
"Regrettably, An Garda Siochana will significantly exceed the budget this year. This is not a sustainable position," he said.
The Garda Band was established shortly after the foundation of An Garda Siochana in 1922.
It was disbanded in 1965 and its 35 full-time members were told to report for ordinary policing duties.
The decision was taken by the then justice minister Brian Lenihan Snr, who said the band had "outlived its usefulness" and the cost of maintaining it was "excessive, wasteful, and out of all proportion to any purpose served".
However, the band was re-established in 1972 to mark the 50th anniversary of An Garda Siochana, and has remained a part of the force ever since.
The garda press office did not respond to a request for comment.
A spokesperson for the IPS confirmed that its pipe band is "mainly self-funding" and that transport, flights, accommodation and other costs outside of the provision of a uniform have been "met from their own funds".
"The Irish Prison Service Pipe Band are excellent ambassadors for the Irish Prison Service and represent the service with distinction," he added.