@Qwormuli
Short answer
Chapter 301: Misuzu's mother encounters Carol for the first time.
Carol: "Good afternoon!"
Mom: "It spoke!"
Is it that odd for her to treat her own daughter like a stranger when the situation allows it?
Long answer
I mean, this is the spoken language, even if we're reading it. There's no reason to use needlessly complicated or wordy sentences to get across what you think, unless that's exactly the type of character you are, which isn't the case for her. Instead, both Misuzu and her mom are established as cynics.
Fact is, Misuzu
is an employee (if only temporary) who
is being unfriendly, while her mom
is a guest (if only to check up on her daughter).
There's no reason why "what an unfriendly employee" would be somehow less appropriate for a cynical mother than an expression that could've been from some instruction manual.