hen pushing eggs out of box

[erinscalli]

Hi...I'm a new chicken owner. I have 6 rhode island red hens and 1 rooster. 2 chickens rarely leave coop to free range with other chickens. they ( or one of them, i don't know ) is pushing the fake eggs out of the nesting boxes and pecking at them. Is this a sign of cannabalism? I have collected any real eggs that where laid in time I guess, because I have never seen them do this with the real eggs ( there have only been 3 laid so far, just got them 2 days ago) Any opinions?suggestions would be appreciated! thank you