The losses if any would be small as they are helped by airport traffic. IE would have no selling point for regular night services on intercity routes and you would need significant numbers to breakeven.
They should be allowed run at certain events free of charge as most people who use intercity bus routes never use the train largely for cost reasons. I mean was it ok for BE to cherry pick their night services after they saw private operators doing so well?
There is a reluctance to run them however I would be happy to see them at least try once and them review and not assume low demand or do those rubbish surveys. Just take the 16.15 to Waterford last March which was ran because they were not going to squeese over 500 passengers onto a 6 coach train. It has ran every week since. There is no way IE would of ever sanctioned such a service unless it was needed and now they are expected to go daily at next timetable change and may even also restore 16.00 up to daily also. The only reason that started was because it was either operate the stock empty at 15.35 and find another 3 coaches to boost capacity on 14.50!