First, you don't have to leave every entry on the list until the end of time. At some point (possibly as a result of the domain being on the blacklist) the attacker is going to discontinue using it and it could then be removed. Second, you don't have to store the blacklist on every client device.
You could even just integrate it with the DNS. If you want to know if foo.com is on the blacklist, you do a lookup for foo.com.blacklist.google.com and if that resolves then it's blacklisted. If you don't trust Google to maintain the blacklist then you change a setting and your computer looks up foo.com.blacklist.microsoft.com or foo.com.blacklist.spamhaus.org or whatever else instead.
The point is to decentralize the decision of who maintains the blacklist, so that users can stop using a blacklist if its maintainer makes unpopular decisions.