First of all, I don't think any kid would admit to having received assistance in writing a college app essay. Second, there are courses available on that very topic - so that would, in effect, be "getting help writing the essay."
And finally, you can't blame colleges for asking (even though no applicant in his right mind would admit it) because these days kids don't know how to write when they graduate from high school. Too many college freshman are testing into remedial reading, writing and math courses their first semester of college.
Makes you wonder what's going on doesn't it? [Of course some of us already have our opinions about what's been going on in public education]