High income parents without sick leave may be able to hire a babysitter. And are far more likely have a job that can be done from home (most "knowledge work")

High income parents without sick leave may be able to hire a babysitter. And are far more likely have a job that can be done from home (most "knowledge work") than requiring physical presence (food service, retail, labor). And are more likely to simply have more leverage with their employers / more rainy day resources to be able to insist on taking a day off anyway and swallow whatever the consequences are.