they the pack them in water - which would definitely attenuate the xrays. I dont speak also spanish that well but my feeling it may also be done to not be picked up in the screening by customs.
I have aslo done loads and loads of research on xray and work with x-ray radiation all day. I am not even convinced that xrays are harmful to eggs. a human fetus less than 21 days old will not be damaged by radiation - mis carriage rates do not go up nor do deformities. There are also studies that show radiation from x-rays at 7 days actually improves hatch rates.
One day when i am old and rich, i will do a double blind randomized clinical trial on it. In the meantime - i make sure xrays do not directly hit my eggs.