No good deed goes unpunished.
I once private FRmailed someone about a word they had misused. I thought they would want to know that the word imply was what they meant rather than the word infer. If I had been making that kind of error I certainly would want to know.
Their response made it clear. They did NOT want to know. LOL
Are you a government K-12 teacher? ( Just wondering.)
Unfortunately, there are a number of participants whose self-image is so poor that merely correcting their grammar or word usage is taken as a blow to the ego, rather than just responding,"You know, you were right and I was wrong. Thanks!"
It gets worse when you find that not only their spelling, but their thinking is also askew, for the same reason -- lack of precision in attention to detail.
With respect --
I once went around the dance floor with a FReeper over the subtle propaganda in the statement: "Most pedophiles are heterosexuals." I stated as much, and told him the proper word was "pederast" (boy-raper).
He then accused me of being a gay activist.