Instacart workers have staged public protests about falling tips, as the CEO is openly pinching pennies. And meal-kit company Blue Apron is trading near its 52-week low after going public earlier this summer. Eat24 will add more scale to GrubHub's network, a factor that the company says helps it compete with other giants. GrubHub spokeswoman Sandra Glading told CNBC earlier this year that the company still believes it has "the broadest, best restaurant network in the space." The convenience will also help Yelp compete with similar integrations at rival TripAdvisor and Groupon.