They find funds and provide marketing, which is astonishingly expensive. I’m not in games, but I do work in a marketing adjacent function. The budgets needed even to do very small marketing exercises are really unbelievable. Campaigns exceed my yearly salary regularly, and we are not doing anything like consumer marketing which I imagine is significantly worse.
Not to justify publisbers’ behaviour, but this is partially why they have such stringent demands, I suspect. I assume they are getting some kind of funding or something from the PSN connection, which funds both the game and the marketing needed to make it a success.