As others have pointed out here, a lottery system with ID can help beat this. Pearl Jam's fan club ticket sales require you to choose ahead of time which concerts you want to go to (max 2 tickets per show) and then on lottery day, you're informed if you won or not and your card is charged. Although a bit opaque, it does make it harder to game the system.
Yeah the fan club sections are always around the stage so if four of you go, although you're not guaranteed to be in the same row/section, you're close-ish.