Javascript. adding items to an array updates all items

This question is somewhat related to this issue I had earlier today:

Adding items to an array in javascript

It works to add items to my array now, but it seems that when I update the array all items will be the same even though the object passed into the method is different everytime

My method looks like this:

addShoe(shoe) {
    console.log("Adding new shoe to collection: ");
    console.log(shoe);
    this.setState(
      {
        shoes: [...this.state.shoes, shoe]
      },
      function() {
        console.log("Shoe collection:");
        console.log(this.state.shoes);
      }
    );
  }

So after one run, this is what the console in Chrome looks like. Which seems to be right:

When I try to add one more to the collection, this is what happens:

Now my collection contains two items which is correct, but it seems like all items in the collection has the same data?

What am I doing wrong here? EDIT

In another React component I have the following state:

this.state = {
      shoe: {
        selectedBrand: "",
        selectedEU: "",
        selectedUS: "",
        selectedUK: "",
        selectedFraction: ""
      }
    };

Once a field is updated with a new value, the following method will be triggered:

 updateSelectedValues(property, event) {
    const shoe = this.state.shoe;
    shoe[property] = event.value;
    this.setState({ shoe: shoe });
  }

When a button in this modal window is closed, the this.state.shoe will be pass as a param to method in the "parent" component.