Easter Egg Shell from HE

Hiya
I got this Easter Egg Shell from Hay Experts FREE. It says you can fill it with hay and herbs for your bunnies. Does this mean that it's safe for the bunnies to gnaw on?

https://www.thehayexperts.com/produ...d=371&osCsid=911374fafabbe0171efcf1af4ff6a672

Hmmm it doesn't say anything about being edible although it states its cardboard. I would be concerned about whether the ink is edible though. Maybe just fill it up and then open it for them on Easter and just give them the treats inside?
You get to use it every year then too

it says on the description bit not designed to be nibbled on