If limes (or anything else, like grass, or strawberries, or potatoes, or mint, ...) happen to grow on your property it's fine and you can collect them, but if you tend to them or there's evidence you planted them it's gardening, and the penalties can be steep.
And police don't look kindly on non-native tasty edibles[0] which "just happen" to grow on the properties of unlicensed owners, as often as not the owner is assumed at fault and fined (though of course the harshest penalties like prison require positive evidence of guilt).
Good grief. Personal attacks will get you banned here. Really, please don't do that, regardless of how nitpicky another comment was or how annoyed you feel.
Is there some sort of water or soil restrictions that warrant the licensing requirement?
I know NZ can be resource limited for a couple of reasons, but I'm trying to imagine why growing things would present enough danger to warrant the law being involved.