If they weren't infringing, the companies wouldn't be paying. It's not like we are talking about some mom and pop that is going to go out of business from legal fees. We are talking major handset manufacturers.
It's not about going out of business, it's about cost/benefit. What good does it do you to avoid paying a million dollars in license fees if it costs you two million dollars in lawyers fees to do it?
(The answer is that it keeps you from being painted as a mark by other trolls. But it still doesn't change the math -- it costs more to fight than to pay.)
