> However, I'm not plugging any extra hardware into them...perhaps that's why I haven't run into problems? Yes. Phone chargers provide plenty of power for the

> However, I'm not plugging any extra hardware into them...perhaps that's why I haven't run into problems? Yes. Phone chargers provide plenty of power for the Pi itself, but once you add several USB devices like wifi/ethernet you'll need beefy ones. But even that is normally not much of a problem, because (especially on the B+) each device has their own port. If you plug several into a hub, however, you'll quickly exceed the hub port's power rating. Hence the need for an active hub.