Or what about the sign below. Doesn't a church pastor have to go to college? I guess the mistake could be justified by the fact that the word "family" is not in the possessive or plural form anyway.
And, just imagine the large number of people who've seen this sign, and then spent the rest of their lives with a gross misunderstanding of what a "toad" was.
I just bring all this up because I know that, just like everyday folks have trouble with word spelling of homonyms, super fantastic authors have the same problems. I've been completely derailed when reading a novel and found just one instance of the mistaking the spelling "There" for "Their" and I can only assume others do too.
That's why editing is so important when writing. I was so obsessive about proper editing that I used an editor for my novel after I performed my own editing eight times. My editor went through the manuscript a few times more finding numerous mistakes in spelling, word usage, tense, and movement at each look. I'm sure there are still some mistakes somewhere within the pages of my novel, but no glaring mistakes (I hope.) It's always best to seek the help of a qualified editor for your work, even if it is just your spouse or parent looking at your homework. Or, you can use "The Perfect Word" editing services and Tammy Parks like I did. Either way it's important to check your work so you look professional. I don't know. I'm just sayin'.