Yes, I have had that happen once. I had a over 200 perfect life fruits, omni plant seeds, and money tree seeds in a treasure chest. Then I moved and lost them all. Back then, I didn't know just reload the game from the last save point, I just saved and quit, I was very upset! Now before I move, I go through every treasure chest I have and put what I don't want to lose in my sims inventory, move, then put it back in the chests. Lesson learned for me, NEVER move without taking what you want to keep out of the chests!