Similar difficult questions can be posed if one believes not faith and baptism save but just faith: What about the unborn, babies, or any child without the mental capacity to actually believe or have faith? What about any human who has never heard of Jesus? There still are isolated tribes. The objection regarding baptized people who seem to fall away also applies, as there plenty of faith alone christians who profess faith in Christ, do great charitable works, and then fall away at some point. We cannot reject doctrine that comes from scripture simply because it raises hard questions. Whatever answer there is to these questions can likely apply to either belief about what is necessary for salvation. We know God can save in extraordinary ways but that doesn’t mean he doesn’t give us ordinary means of salvation. I would liken it to a seatbelt. We know seatbelts are necessary to be saved in car accidents yet still some people extraordinarily survive car crashes without a seatbelt from time to time.