The coil is part of the pod and therefore user-replaceable. The point of a pod system is to keep the coil and liquid in a self-contained system, which practically eliminates the risk of liquid leaks. All of these quasi-disposable vapes with replaceable pods and a charging port can be re-used hundreds of times.

I don't know why people dispose of the whole thing rather than just changing the pod, but at least it's a boon for electronics hobbyists.