The theory is that if Google doesn't give DMOZ all the love that Google gives it, that no webmaster would want to pay for a link there.
Normally if a directory gets penalized the directories cached pages are removed after the brand name. It sometimes takes up to two weeks for all the cached pages to be removed but I don’t think you will see this with DMOZ. They have been caught in filters in the past and it has always been corrected within a month.