What would you do if your dog refused to eat his food?

My dog will not eat his food. He will beg for our food, will eat a treat but will not touch his food. He's been checked by a vet, nothing is wrong with him. Vet says he's probably just picky. Is it cruel of me not to make sure he eats his food? He was begging for our food, so I tried to feed him but he turned his nose up. He's always been picky. He hasn't eaten in since Wednesday and it's Friday night. I have fed him with a spoon before because I just felt awful that he hadnt eaten but I don't want to do that. I just feel cruel not trying everything possible to get him to eat his food.