Why won't my dogs eat?

We have four dogs. (Of course we do...don't all lesbians have at least four?) Two older ones (12 yrs) and two pups (18 mos. and 9 mos.). Hunny and Geea (the older dogs) are  very dogly dogs. Especially with respect to their food. We prepare it; they eat it. Anytime, anywhere. They eat it all. Up. And lick the bowl. And would eat more whenever we give it to them. Dogs. As they should be. But, the two pups are just weird. At dinner time, rather than standing there, at our feet, drooling, waiting for the homemade dog food to get warmed up in their bowls, they run out to the big back yard and start playing!?! What!?! There we are, the dog-moms, holding two big, full dog bowls, yelling for our silly puppies to come and eat. They are big dogs. The 'little' one is over 50 lbs, and Kai probably tips the scale at 110 these days. They should be hungry. They finally come up to the deck and look at their food. Not 'gobble it up' or 'wolf it down' or 'scarf it down' - no, they look at it, sniff (maybe), walk away, look up at us questioningly, anything but eat. And it's not that they don't like their food; we've tried all kibble, no kibble, homemade with chicken, homemade with beef, with and without spices, with and without water, changing bowls, etc. We thought maybe the older dogs that really like to eat were terrorizing them somehow (dirty looks, or threats when we weren't looking), so we tried to feed them separate, for example, in the kitchen or bathroom. (The dogs usually eat on the back deck.) They just got so nervous and didn't eat then either. The only way they actually will eat is if we hand feed little bits of their food at a time. Not much fun for us, as our hands get all dog-foody! Yech! They couldn't just be spoiled rotten, could they?