Can chickens eat air pellets?

No, and they should not. The hard plastic is indigestible and could get stuck in the digestive system of the bird, ultimately killing it. It is unlikely the chicken would even bother eating a hard piece of plastic anyway, but if the bird dies and the farmer who owns the bird happens to clean the bird in preparation to eat it he may very well find out what killed the bird and know where the air soft pellets came from....big trouble in the barnyard at that point. You should be more careful where you use them.