Agreed. "Dessert" vs "desert" - mistaking these two is often not a grammatical error (they're both nouns), but is a spelling error (they have quite different meanings, and the person who wrote the word simply spelled it wrongly).

I agree, but this is definitely the kind of spelling error (along with complementary/complimentary, discrete/discreet, etc.) that we normally don't expect our spellcheckers to catch.