I think it's fantastic. Although I have access to Premium Dom check-in, I have never used it once because 1) I can check-in at the NZ car parking and 2) it is so easy on the machine. There are a number of people who struggle with the technology, which is exected, but NZ always has ample number of staff to help out. I personally think it is best suited to the major domestic airports in NZ and the problems you outline earlier are why many of the regional airports have only 1-2 check-in machines and just do it manually; many of the pax at these airports are travelling onto intl connections and must be checked in manually.

I'd say once the whingers see how fast it is to do it themselves, they won't be complaining about not having someone to do it for them. But hey, you can't please everyone.