[amyjess]

At least part of it is to keep civil.

There are memes floating around that joke that common businesspeak phrases like this are just polite ways to phrase insults, and that's only a little bit of an exaggeration. In my experience, when someone says "as per my last email", it is a very thinly-veiled version of "are you too stupid to understand what I just told you?".

But you have to keep civil in a business environment because a) money is on the line and b) you're going to have to keep interacting with the same people for a long time.