The disadvantage to that is my cat. I give her half a can of cat food twice a day: around 7AM and around 7PM. She also has dry food if she gets hungry in between.
At around 5AM, if the bedroom door is open, she will come in and meow at me: "feed me!"
Then I will get out of bed and go into the kitchen. My cat will follow me into the kitchen, and then run on ahead into the extention where I usually feed her.
Then I close the door between the kitchen and the extention, leaving her in the extention, without feeding her. And go back to bed for a couple of hours.
I keep thinking that either (a) she will learn not to wake me or (b) she will learn not to go into the extention until I actually feed her. So far, she has shown no signs of doing so.
I could lock her in the extention before I go to bed and forestall this whole thing, but she's often hard to locate late in the evening anyway. And she always goes into the extention unprompted in the morning. So. It works. At least until she works out (a) or (b).