There isn't a need to always point out grammar mistakes. Simple ones like: "The thing is, <--comma I have" are being very nit-picky and are not constructive to the forum. Remember there are many people on here all with different backgrounds and, very important, different ages. Grammar is hard for some people out there, and if you are very good at it that is great, but there is no need to point out others mistakes.
Don't put down others to raise you up!
It isn't a competition on the site who can spelling the best
And telling me (or the person) "I was only trying to help" is a poor excuse. You are not their teacher.
Just let the little things go guys!