No it's not too late!
Right about now is when employers discover which of their summer workers bailed or are totally worthless. I promise you there are vacancies.
Child-centered businesses are ALWAYS looking for summer help. You know, places that do summer programs for kids like swim/tennis clubs, horse riding camp, YMCA, community centers, etc. And there's always hospitality jobs available...food service, cleaning hotel rooms, etc. Don't limit yourself to fast food. Apply to sit-down restaurants too. They need dishwashers, hosts, etc.