people are enjoying food at a crowded restaurant.
A lone person eats sadly at a truck-stop in the middle of nowhere.
There cannot be both a person and people, they are either enjoying or eat sadly but not both, and they cannot be at a restaurant and a truck-stop at the same time.
A lone person is not people.  Enjoying food is the opposite of eats sadly.
THE LONE PERSON EATING SADLY IS CONTRADICTORY TO PEOPLE ENJOYING FOOD