Chess is a game where there is no knowledge gap on the board, both sides know 100% of the game state, and I feel like that's generally not the type of game that interests me as it removes much of the human aspect of reading and conditioning an opponent.
I've bought ~$200 worth of Persona titles thanks to video of Persona 4 on the internet. Hell, I bought a Vita pretty much just for P4G. I might be in the minority here but this idea that people are just going to watch a let's play instead of actually buying the game is a pretty ass-backwards one. I have to imagine there are countless people on this site alone who would have no interest in Persona 5 if it wasn't for the Endurance Run of P4.