AdvancedTableViewCells code example problem

Question

So apple has this pretty cool example about how to make a uitableview which cells resemble appStore cells. Code can be found here.

Now, the strange thing... I was playing with it, and in RootViewController.m where it was

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Configure the table view.
    self.tableView.rowHeight = 73.0;
    self.tableView.backgroundColor = DARK_BACKGROUND;
    self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;

    // Load the data.
    NSString *dataPath = [[NSBundle mainBundle] pathForResource:@"Data" ofType:@"plist"];
    self.data = [NSArray arrayWithContentsOfFile:dataPath];
}

I putted

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Configure the table view.
    self.tableView.rowHeight = 73.0;
    self.tableView.backgroundColor = [UIColor groupTableViewBackgroundColor];
    self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;

    // Load the data.
    NSString *dataPath = [[NSBundle mainBundle] pathForResource:@"Data" ofType:@"plist"];
    self.data = [NSArray arrayWithContentsOfFile:dataPath];
}

Basically, I've changed the tableView's background.

And... the cell's images (the applications' icons) disappeared. But they are there (they show when I select a cell).

Honestly, I don't know why, but I kind of would like to know, for it makes no sense to me. Any clue?

Thanks a lot.