It's better to send fruit in the cans, with pop-top lids. The plastic cups are very prone to breakage. Think of this: I sent a well packed box, all chunky soup solid cans; no shifting of contents was possible. It was returned (because the post office mis-read my directions on the customs form). Every single can was dented. The box was also full of the talc-powder-like dust even though every opening and seam had been sealed with dust. So if solid metal cans get dented, expect the plastic cups to break.
Anything liquid should be in DOUBLE zip-locked baggies.
Thanks for the info. I guess some drippy packages arrived :o(