Money Tree ?

I went for a walk by one of our local bays. Petit Bot which I think translates as "little bay".  There is a small cafe just before the entrance to the beach, that is only open in the summer. In the rear garden is this tree stump?, the note says "They say that money doesn't grow on trees but maybe it could on wood? "  I think its a large money box as it also says all contributions gratefully received. The sign is from the charity "Mind". I also took a walk along the beach, the tide was out and all I had for company were a few gulls. I would imagine it will be packed in about three months time when summer is here.