The first is that it has a camera with a large fisheye that can show you the inside (though this is more useful when away from the fridge rather than using the screen). The issue is the camera is only at one point. The fisheye helps see more, but it can never see all the fridge.
The second is as a home assistant in the kitchen. This is actually useful. It can display recipes and whatever in it whole you cook. You can also use a phone, tablet, or other home assistant device for this though, but if you want to throw away money this does seem convenient.
They also can show arbitrary stuff, so it's great for todos, family reminders, etc. We bought a chalkboard-like thing (wet chalk?), but a thin whiteboard would work too.
My wife prefers using a tablet to cook since she can move it around (from the prep counter to next to the stove). I use my phone.
We bought a new fridge recently, and while the smart features looked cool, I don't trust them to get security updates, nor am I willing to pay a premium for cool features on a fridge that's likely to have problems (Samsung and LG have the coolest features and the worst repair track records).