You just don't know who in the real world might be picking up your phone sometime and seeing whom you've dialed, or a call from an escort could come at some inopportune time.

But if you don't have an SO, it's not nearly as big a deal.

I am now single and just use one phone, for example.

However, I rarely carry my phone with me, prefering to be reached at work or home on a land line.

Just old fashion, I guess.