Spelling gets a lot of attention in school.
Sometimes this attention is warranted and other times this attention can be destructive.
Too often, spelling is easy to count so it counts for a lot. After all, quantifying creative and imaginative writing is a hell-of-a-lot harder than counting spelling errors.
Remember that spelling is a means to an end - communication. And if kids aren't inspired to communicate through reading or writing, why would they ever feel the need to spell anything correctly? Out-of-context and in isolation, spelling is a useless skill.
I don't know too many people who are inspired to read and write because they want to spell. It's got to be the other way around.