I never felt the need for a rice cooker until I started cooking Japanese rice.
Japanese rice (Koshihikari) is quite different from, say, Basmati and other "normal" long grain rice.
It absorbs water in a 1:1 ratio rather than 2:1, and comes out dense and with a meaty texture.
Every time I try to cook Japanese rice in a pan on the stove, I burn the bottom.
But in a cooker, you wash the rice, you put it in the cooker with the correct amount of water and a couple of pieces of dried kelp (kombu), close it and a few minutes later it's done, and it comes out perfect every time. Just a bit sticky to help with the chopsticks.
I don't know about cake baking?