spelling people, spelling. or is it grammar?

Let me start off by saying that I basically cannot type and my spelling skills are, well, lacking.

BUT. I proofread my blog posts and work in general. And I know when to use which of the there/their/they're choices. And I spell check. Thank God for spell check.

What drives me nuts, and I mean nuts, is when I am reading something interesting, and then all of a sudden the wrong there/their/they're choice is they're.

See what I mean?

Pay attention people! Please.