I'm not arguing that bypassing the WSJ paywall causes damage to WSJ - I'm personally not sure that it does. What I'm arguing for is that if for some reason WSJ needed to prove in court that a paywall-bypassing tool causes them damage, they would use the it-deprived-us-of-potential-revenue argument that I outlined, rather than the it-forced-us-to-waste-electricity argument. You're right that the it-deprived-us-of-potential-revenue argument might not work in this case, in the sense that it is very possible that there does not exist a person who would have paid for a WSJ subscription but, because of the paywall-bypassing tool, did not.