Mailman Crons

I've seen that Mailman does a bunch of stuff more than just emailing, on the crons I've seen some digest send, tar gzip archives.. etc

But those seem to be just silly things to eat up a bunch of cpu and saving useless data. If I disable all the mailman crons, will it affect anyhow the mailing itself ?

Or it will only loose some features like gzipped archives (i'd like to delete them, not to zip'em), those emails saying "do you want to be still listed here?" that allways fill up my queue list and turn my load to the sky...

It would be good also to have some sort of Administration panel because for me Mailman is like "it's there" and just that.

 

What does the crons exactly do ?
Is it wrong to disable them ?