SIGG bottles are tough, don’t leak and are safe. They’re good for the environment and economical. You can fill up your reusable bottle at the office water cooler, or at the filtered water stand beside the camel outpost. Aside from the convenience of having one of these anyways, in some cultures (e.g. in a desert) you may find yourself in a mandatory BYO water bottle situation. Repeatedly re-using single use water bottles (e.g. PET plastic bottles) can be quite nasty over time, as bacteria will build up in the bottle.