Rituals are great. They are the affirmation that you're a team, and that the team is almost a living organism. It has a heartbeat and habits - and those are your rituals.
Rituals are only affirming if they continue to have meaning. There's no point to having a retrospective if you're no longer coming to small stopping points every iteration. Otherwise it's just a standup, only longer; you can't retrospect in the middle of something. There's no point to having donuts on Wednesdays if you're forced to bring them in; the beauty of that ritual is the small thrill of informality.
Embrace the rituals you have. But evaluate them to make sure there is still meaning behind your rituals. As soon as they lose their meaning, stop doing them. There is no affirmation in empty rituals.