I think you're right. Good catch.
For the past decade or so, many parents have had to drive their kids to and from work for financial reasons. Parents with higher incomes don't understand. They can afford to pay the extra cost for Junior to drive. They might even buy Junior his first car. The rest of us cannot, so we end up giving our adult kids rides until they can afford everything on their own. I knew many families in that situation. I worked with young adults who got rides from their parents. They gave their paychecks to their parents, too. They were helping to support their families.
Also, approximately 20% of Gen Zers from 18 to 27 are still teenagers, most likely to be living at home while seeking a job, whether or not they sometimes live at college.
If you work out the math of those involving parents times those of that subset taking parents in to interviews, it comes out to 8%, which is only 80% of the 18-year-olds in the studied population.