don't know but my cat is the ame. she meow's and meow's until i go overto her by her food and then she startsto eat. what I have started doing is briging her food into the living room.
One of my dogs is the same but with him he's not particularly driven by food and just thinks I must be doing something more interesting if I'm not there so he comes looking for me. Mealwhile the other dog (opportunist old lurcher) polishes off both meals!
I have two dogs. If I leave them food when I go out they won't eat it until I return.
I have often wondered why, so I can't answer you're question but now I'm really curious.
It's probably got something to do with you being the pack leader. In the wild the leader eats first, the others eat only when allowed once the leader has finished. My German Shepherd eats like he's starving as soon as my husband comes home from work even thought the food has been there all day.
My cat is the same. Read somewhere once that cats feel exposed to attack while they are off guard with their head down eating, and they like you to "watch their back" for them. Could be the same for dogs I suppose.