Agree 100%. A tip is entirely optional in NZ, and servers are paid the same as anyone else. Service is not always as prompt and butt-kissy here, I must admit - but they also don't try to hustle you out the door so they can turn the table, either. Service is definitely not as good as in the US though, in general. Better, in better restaurants, as you'd expect.
Service varies a lot on where you are. It's much better in the south. It's better in Seattle than it is in Portland, and it's better in Portland than it is in Los Angeles, and it's better in Los Angeles than it is in Vancouver BC and it's better in San Francisco than everywhere listed above. There's a very real reason to tip well - if you're at the establishment regularly, getting a regular waiter or waitress who knows you're worth serving is stellar. You get the good table, you get prompt service, you get personal attention, if you mention it's an occasion they'll hook you up with little treats, etc. In Hollywood, where "lunch" is where things happen, it's entirely appropriate to have a good line on a good waiter in a good restaurant because having the meal go well helps having the deal go well. But there's a world of difference between tipping "extra" - 5%-10% - for that kind of service and the basic, surly not-paying-attention you get at Applebee's. Yet if I pay 25% at Kate M's I'm paying $7.50 and if I pay 20% at Applebee's I'm paying $4. So really, the actual tip between "you suck" and "you rule" is $3.50. And that's bullshit.
Portland's service is terrible. In other places I have lived a server makes $2.15 an hour, in Portland they make $9 an hour. The higher minimum for servers here disincentivizes hustling to pay your rent. A good cook might make more then $10 an hour if they are lucky here, but $11-12 is pretty standard in the rest of the nation. Cooks starve so that servers can take home $20-30 an hour with the minimum subsidy. As someone who works service 15% is fine, even if I am giving top notch service to demanding people I don't mind a 15% tip. At the bar tip a dollar a drink or drink beer. Your pours will be shit if you tip any less. As a bartender the dollar a drink is fine but I don't really care all that much, it's the $20-$100 dollar tips that really line my pockets. Why people tip 100-500% is a mystery to me, but I will treat you like a fucking king if you are that guy or gal.
That's you, though. I regularly read or hear complaints from those who argue that 15% is insulting. Not only that, but now you're saying 15% is okay... when the base wage is 4x as high as it is elsewhere! Which is something that has never been made known to me in all the times I've dined in Portland. The system sucks. It's a terrible maladaptation of free market principles.As someone who works service 15% is fine, even if I am giving top notch service to demanding people I don't mind a 15% tip.