Or maybe she was not the type to turn of her position as manager just because she was off of the clock. Not everything is about race and playing the race card and having a drink splashed on you can be angering.
You are right. Sometimes we (myself included) are way too quick to make judgments based on race. I read this sentence and my BS meter goes off. Read between the lines and maybe what happened is this mother threw a drink at the manager because she was pissed off and the manager overreacted and punched her.