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)


{
    if (ui->buttonBox->buttonRole(button) == QDialogButtonBox::AcceptRole)
        done(QDialog::Accepted); 
}
void CoinControlDialog::buttonSelectAllClicked()
{
    Qt::CheckState state = Qt::Checked;
    for (int i = 0; i < ui->treeWidget->topLevelItemCount(); i++)
    {
        if (ui->treeWidget->topLevelItem(i)->checkState(COLUMN_CHECKBOX) != Qt::Unchecked)
        {
            state = Qt::Unchecked;
            break;
        }
    }
    ui->treeWidget->setEnabled(false);
    for (int i = 0; i < ui->treeWidget->topLevelItemCount(); i++)
            if (ui->treeWidget->topLevelItem(i)->checkState(COLUMN_CHECKBOX) != state)
                ui->treeWidget->topLevelItem(i)->setCheckState(COLUMN_CHECKBOX, state);
    ui->treeWidget->setEnabled(true);
    if (state == Qt::Unchecked)
        coinControl()->UnSelectAll(); 
    CoinControlDialog::updateLabels(model, this);
}
void CoinControlDialog::showMenu(const QPoint &point)