What are you feeding? Is there enough food available? Perhaps, if you are feeding seed, there are too many hulls in the way?
Mine do this, too, they are on pellets, though and only do this when they have a seed treat. Then they sometimes goof around in the large dish.
I am sure it also could be related to some instinctual behavior, so I feel that there is nothing to do, but make sure there is the right amount of food available and let it go as far as feeling that they are behaving naughtily.
So, if you feed seed, check it morning and afternoon for hulls, carefully blow off the hulls (or take two small containers and pour the seeds from one to another and let the wind carry the hulls away).
If they are transitioning to pellets, they could be fussing around, so make sure they have enough food to eat and try putting the pellets on a mirror (a plastic one you can get at the Dollar Store is really safe) and as my vet explained and showed me, they will eat pellets off the mirror because they think "the other bird" is eating them. Mind games on budgies!