said by cowboyro:
Why in the world would someone use both options?
Once upon a time when I elected to receive work emails on my person phone, I liked to quickly preview emails while I was not in the office, but then go through them individually when I was back in the office. Seeing if they were read or unread at the office was convenient even if I really had read them out of the office.
That's a little different then in this circumstance, but I could see some usefulness.