I went along to this.
Two points stood out for me:
Unions are sticking to the line that based on CSO statistics (6 months out of date) there is no evidence of private sector wage cuts, so why should their members take wage cuts.
They were quite serious on this point, que much heckling from audience.
Unions also mentioned that the government dont' have a mandate for wage cuts.
It was pointed out by one audience member that the government were elected but he didn't vote for unions, much to the annoyance of union rep.
While I'd have sympathy for protection people from exploitation etc, unions are living in parallel universe, they really, really don't get what's going on.