You've also got to remember that not a lot happens in Ireland - so all the local newspapers tend to put out song lyrics, which are usually absorbed into the tradition if they are good enough. The Irish Post does a special Christmas number with the best songs of the year published in it. And there are an awful lot of songs written by ex-pat Irishmen on building sites in London because they can't find anything better to do (eg. And down the glen came MacAlpine's men). My memory says that there were two theatres in Dublin, and one in Cork, in Victorian times. But most "music hall" performances were staged in geggies (portable tented theatres) that travelled the country staging performances at 1d per person, 1/2d for children - so while the shows were there, the music halls were not.