Bad guy

Why does the onus have to be on me to interpret your grammatical error in such a way that it makes sense? I could be a real bitch about it and tell you I have no idea what you’re saying, but I can tell you how that conversation would turn out. “You know what I meant. Geez, what are you so sticky on grammar for?” Then I’m the bad guy for “making you” feel stupid, thus eliciting a defensive reaction in which you would feel the need to put me down. Why should I be the bad guy when you’re the one who types a sentence that mistakes “once” for “ones”?