The first reason given, "more communication options," is surely not the primary reason.
If I were still teaching, I think I would use this as an excellent example of how markets tend to address things that bother people. Junk calls are annoying. But, in my case, about 70% of the annoyance is removed by having caller ID. Another 20% is removed by having multiple phones with multiple phone numbers, which are now cheap, including one that almost no one has and I can reserve for important callers. And the remaining annoyance could be all but eliminated by using my home phone's mute button. I haven't used it yet, but with election season rapidly approaching, I may.