This is it - if you hear the word "wary" and know the verb "to wear" before encountering the written word "weary" it's totally understandable to assume that is how "wary" is written and to mix them up.

What I wanted to do with my comment is show this without coming across as a mean or pedantic - especially since in the context both work ok. I've no idea if I accomplished that, I probably come across as a dick but I hope I don't.