I mentally filed this away as something needing further investigation as my recollection of Parliament Street in Cork was a similar word to Parliament. Tearma.ie confirmed Feis is a festival or feast - as in Feis Cheoil or Ard-Fheis.
Yesterday, Logainm.ie’s update was on Parliament Street in Waterford – the Irish translation for this and the three other Parliament Streets throughout the country is Sráid na Parlaiminte.
ComeHereToMe advises that Parliament Row was called Turnstile Alley upto 1775.
Maybe the turnstiles were an entrance to a feast or a festival. Or maybe, those in Temple Bar equate those in parliament to feasting for themselves. I suspect that there is a better explanation – but that remains on the ‘To Find Out More’ list.