Their argument is that the TPPA is not council business and should not have been on the agenda, and it is a position that has some merit.
Undoubtedly, the proposed trade agreement is primarily an issue for central government. However, should it be passed into law, its ramifications will almost certainly drip down to local governance, and other district councils have accepted submissions and resolutions on it.
As our elected representatives, councillors are no doubt approached on all sorts of matters by Wanganui ratepayers, a number of which will not be the direct business of a district council but which should be more appropriately dealt with by central government, the district health board or other bodies.
However, one assumes they will give these ratepayers a hearing and direct them as best they can. It would seem to be common courtesy to those who pay your remuneration - and it's a courtesy that was lacking at the council chamber on Thursday.
If they didn't think the TPPA was council business, the foursome had the chance to vote against the resolution or abstain.
Their boycott may prove a drain on time and money as Mayor Annette Main has said the issue will be brought back to the table.
The schism among our representatives is particularly worrying because apparently the walk-out was signalled in advance if the TPPA item was on the agenda.
A serious negotiation - and some compromise - is needed by all councillors so that an agreement is reached on how this matter is dealt with in the future. That would allow members to vote as they saw fit but would spare those who brought the submission to council being treated so badly.
And it would spare the community seeing its council split in two.