Why don't people like software patents? Because their power (total monopoly over an idea) is out of sync with the difficultly in acquiring one (stick an engineer in a room with a notepad for 10 minutes, then get a few lawyers to translate it into legal hieroglyphics).

But you are correct that nobody really cares when the defendant is a multi-billion dollar company. Facebook can look after themselves just fine. If Yahoo were suing a startup, the backlash would be far stronger.