NET_RX_DROP vs dev->stats.rx_dropped++ in drivers

We have noticed odd dropped packets in a few cases and these comes from
drivers that do this:
...
	dropped = netif_rx(sb);
	if (dropped == NET_RX_DROP) {
		dev->stats.rx_dropped++;
...

This seems a bit odd to me, should drivers account for dropped pkgs in this case?

 Jocke