Another good one is if you are into homebrew computers or are a computer or electrical engineer. Perhaps you would like to make your own processor, or collaborate with your friends on making a processor.
As a half-joke, half-serious question: how do you know that Lattice isn't backdooring all their FPGAs, sending home everything you run through their bird-drone network?
I do not want exactly what you are suggesting. What I am into is homebrew computing and trusted compute. I can't have either of these things by just getting a zynq board. The game issue, as you noted, is quite trivial to solve.