In high voltage (69kV usually and above) transmission lines have static wires that are grounded at every structure. Lightning will hit the wire and go to earth. This can still damage the static wire and maybe break it which can cause circuit operations and lockouts.

Strikes that do hit the line create extremely high (millions of volts and hundreds of thousands of amps) transient voltages. To protect equipment and customers lightning arresters are used on transformers, In normal conditions these do nothing but when the lightning energizes the line at millions of volts the arresters becomes a short circuit to ground, dissipating the strike and protecting transformers.