Kathy, you should still bother. An item will only tarnish as much as an air supply will let it. Besides, the limited tarnishing should be more even and not spotty as it would be near an air leak.
As for my own collection, I really don't clean any of them until I'm ready to dispose of one or show it off. I have this uneasy feeling that maybe a token can be cleaned only so many times. Plus it seems that with each cleaning, it re-tarnishes quicker each time. I think the natural patina or original tarnish protects the token somewhat.
I don't have any real reason for believing as I do. It's just a preference.