Does it matter?

I received an email at work last week about work and for some reason I couldn't get past the word DEACON. Now I think I know what that says. But perhaps I don't. the subject was about the VA Hospital and its emergency response team. A group of people who have volunteered to go to disasters to provide releif when needed. The subject was the decontamination team and upcoming training. Now the word DECON has a lot of meaning to me and many others who served in the military. It was always an individual common task for every soldier in the Army. Which takes me to DEACON, a position in many christian churches and I don't think it is interchangable with DECON.
I was reading about a construction project that recently had the ground breaking ceremony at Arlington National Cemetary. A new building for the inturnment of those who would prefer a mosoleum instead of being burried in the ground. There are currently 5 such buildings at ANC. The author of the story used the word INURNMENT when refering to the burial or placing of a casket in a mosoleum several times.
Does it matter if the correct terminology or grammar is used in correspondence? Does it matter if an author does not know the difference between their, there or they're. All come up correct using spell check. However "that is their property" is correct and "that is there property" is not correct. Your wasting your time or you're wasting your time. Get it?