That's not how trolling works. Your out of pocket cost for patent prosecution is maybe $20K or $30K per. If you want to litigate, you enter into a contingency or mixed-fee arrangement with a plaintiff firm and possibly also a litigation financier, depending upon the size of your pocketbook and your appetite for risk. Your lawyers build up a war chest by shaking down easy targets until it's big enough that they can lay siege to a big opponent. It's become more difficult to do this than it used to be due to recent developments in patent law, but it's still eminently possible and happens all the time. This is, in fact, how plaintiff litigation works in a number of other civil case types.