Rewards are useful to me only when they fit the session I already planned. I did not want to raise my stake just because an offer was available. During a low-stake UK slots session, I checked
https://fatpirate.uk.com/ after the first game and compared the reward details with another slot I wanted to try. That made the offer easier to understand. I used it as extra room, not as a reason to chase bigger wins. The session lasted longer, but it still felt controlled. In that sense, the rewards did make the slot play better.