There's no harm in giving them out. If the particular crew member shares CIHY's views on the scheme they don't have to hand them to their manager. If they appreciate the scheme they will hand them to their manager.

Different people value different things and also I believe all managers are different.

If I was a manager I'd never expect an employee to sacrifice a day off unless it was an urgent disciplinary matter that needed dealt with ASAP, I certainly wouldn't expect them to come in to say well done. I'd find a different time to do it where the inconvenience was minimised.