I think people worry more about rust than they should. Yes, if you leave your carbon steel knife immersed in water for a long time, it will rust. Yes, if you don't pay any attention to the care and maintenance of your equipment, it will begin to degrade. That's not just knives, it's everything. People all over the world, from jungle to desert to tundra, have used carbon steels for many centuries. If you use your knife/machete/axe/anything else regularly, that will serve to deter most rust. If you're not going to use it regularly, a simple wipe down and some oil will keep it from rusting. I have lots of carbon steel tools, and live in a humid, swampy area, but have had no issues with rust on them. In short, give your tools the tiny bit of love and attention they require, and don't fret too much about it.