I too come from a country (New Zealand) where staff are paid a reasonable wage and it is not normal to tip for normal service, although you can do so if you get great service. I've never heard of anyone being encountering aggressive tip requests.

One things that does confuse me when reading posts in this topic is how when people receive really bad service they still give a tip, just at a lower percentage. Why do they do this? How bad must the service be for someone to not tip for the service?