I don't think those are even close to equivalent. The enjoyment from video games does not come from a hope of it "paying out." The fun of gambling is usually from the chance of getting a reward. If the reward were not there, would they still enjoy it? Probably not, so they're not just enjoying the act. Sure, there's some dopamine release that's driving the behavior, which is enjoyable, but there are methods to get this with better EV and more rationally.