Getting governments to change laws to protect your profits. A classic example of this is taxi cartels, enforced by medallion systems - it's bad for cabbies, astonishingly bad for users, not great for new entrants to the system(and bankruptcy-inducing if they ever unwind the system), but the guys who paid a hundred bucks for a medallion in 1950 and sell them for half a million today earned a gargantuan profit for no good reason except regulatory capture.