There are three things that people pick up on the instant they walk into your home on Thanksgiving. They will be able to feel the human energy. They'll smell the food. And they will see, instantly, the table.
Long before Starbucks popularized the phrase 'the third place' - somewhere to interact outside of work and home - it was neighborhood restaurants that helped to define places like Union Square.
A great restaurant is one that just makes you feel like you're not sure whether you went out or you came home and confuses you. If it can do both of those things at the same time, you're hooked.
If somebody doesn't want to cook at home or has more family members than they have room for, then it's great to be in a city that's got restaurants that are actually busy on the holidays.