I am round, sweet, and sometimes I hide a message inside. What am I?

What bag gets smaller every time you use it?

What cake tells you how old someone is?

I have a crust but I am not the Earth. I can be sliced but I do not bleed. What am I?

What moon can you eat before it becomes full?

I disappear from the table fastest, even though nobody chases me. What am I?

I look like a horn overflowing with fruit and vegetables. What am I?

I have many eyes but cannot see. I grow underground. What am I?

I am cold, sweet and disappear if you leave me in the sun. What am I?