Maybe they have some purpose, but it isn't immediately obvious. I tried Tree & List mode, they're never populated.

![image](https://user-images.githubusercontent.com/13134193/33488849-04a2c8a6-d6ed-11e7-85c3-5c05f1ec5346.png)

* Bitcoin-Qt 0.15.1 for Ubuntu 16.04 x64 (from http://ppa.launchpad.net/bitcoin/bitcoin/ubuntu xenial/main amd64)

Note: I just noticed I'm *not* seeing this on Ubuntu 17.10 x64 with 0.15.1 downloaded from bitcoincore.org. 

![image](https://user-images.githubusercontent.com/13134193/33491553-9584dc62-d6f5-11e7-9ba7-e074e0e36151.png)


{
    static CCoinControl coin_control;
    return &coin_control;
}
void CoinControlDialog::updateView()
{
    if (!model || !model->getOptionsModel() || !model->getAddressTableModel())
        return;
    bool treeMode = ui->radioTreeMode->isChecked();
    ui->treeWidget->clear();
    ui->treeWidget->setEnabled(false); 
    ui->treeWidget->setAlternatingRowColors(!treeMode);
    QFlags<Qt::ItemFlag> flgCheckbox = Qt::ItemIsSelectable | Qt::ItemIsEnabled | Qt::ItemIsUserCheckable;
    QFlags<Qt::ItemFlag> flgTristate = Qt::ItemIsSelectable | Qt::ItemIsEnabled | Qt::ItemIsUserCheckable | Qt::ItemIsTristate;
    int nDisplayUnit = model->getOptionsModel()->getDisplayUnit();
    for (const auto& coins : model->wallet().listCoins()) {
        CCoinControlWidgetItem *itemWalletAddress = new CCoinControlWidgetItem();
        itemWalletAddress->setCheckState(COLUMN_CHECKBOX, Qt::Unchecked);
        QString sWalletAddress = QString::fromStdString(EncodeDestination(coins.first));
        QString sWalletLabel = model->getAddressTableModel()->labelForAddress(sWalletAddress);
        if (sWalletLabel.isEmpty())
            sWalletLabel = tr("(no label)");
        if (treeMode)