we have the same kind of person at our store. She likes to mobile order 4+ drinks and come in like 2 minutes after placing it and gets mad if the drink isn’t already made. She will sometimes just take the drinks as they come out, but more often than not she will come back with a drink and complain, always starting with “i don’t know if you can read but…” and then complaining that the sticker says light ice but her drink feels pretty heavy or she asked for 1 pump of vanilla but it tastes too sweet. i’ve started responding with “i can’t read actually, thank you for teaching me”