If Ireland would lose the economic advantages of membership from one day to the next, probably most of those Euroskeptics would be the ones to complain loudest of all ...

Some would be quite happy to retreat to an older, more conservative, religious, monocultural and "pure" Ireland.  Some imagine the can secure more power and influence within the nation state than they can within the EU as a whole.  Some see the EU as part of the global capitalist conspiracy to take over the world. Some are "following the money" and ingratiating themselves with their US masters.  Most are just pandering to the frustrations that many people feel in a rapidly changing society.  The problem is there isn't a coherent set of "NO" issues which can be addressed, and therefore no obvious solution to the impasse in EU development.

"It's a mystery to me - the game commences, For the usual fee - plus expenses, Confidential information - it's in my diary..."