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)


#ifndef BITCOIN_QT_COINCONTROLDIALOG_H
#define BITCOIN_QT_COINCONTROLDIALOG_H
#include <amount.h>
#include <QAbstractButton>
#include <QAction>
#include <QDialog>
#include <QList>
#include <QMenu>
#include <QPoint>
#include <QString>
#include <QTreeWidgetItem>
class PlatformStyle;
class WalletModel;
class CCoinControl;
namespace Ui {
    class CoinControlDialog;
}
#define ASYMP_UTF8 "\xE2\x89\x88"
class CCoinControlWidgetItem : public QTreeWidgetItem
{
public:
    explicit CCoinControlWidgetItem(QTreeWidget *parent, int type = Type) : QTreeWidgetItem(parent, type) {}
    explicit CCoinControlWidgetItem(int type = Type) : QTreeWidgetItem(type) {}
    explicit CCoinControlWidgetItem(QTreeWidgetItem *parent, int type = Type) : QTreeWidgetItem(parent, type) {}
    bool operator<(const QTreeWidgetItem &other) const;
};
class CoinControlDialog : public QDialog