Visitor shook and took my bells tree

I had an open session earlier today (in another r/) about 10 people came. I gave out at least 2mil by dropping on the floor + others item. One did asks if he can get fruit, I said yes go shake it down. But after I closed I realise that some money tree are shook and the money is gone. Also rare mushrooms that I drop for decoration is also gone. I really don’t care about the fruit and veggies but isn’t money tree suppose to be leave as is? I did gave out bells too. Is it my fault that I didn’t specify in the post ? Is it not a protocol to at least ask first? I’m not mad just curious if I have to specify everything from now on.