Now I wonder if some birds will fool other birds by pretending something isn't good.
Seeing this, I could imagine birds using the strategy you describe.
How would they do that? If other birds are watching to see if they eat the food, it seems that your options (as a deceptive bird) are not to eat it (in which case they might be fooled, but you lose the food) or to eat it (in which case they aren't fooled—they aren't looking for your subsequent review of the prey!).