This is the reason why I've put the altcoin/bounty sections on ignore, but I've visited there to report some of these kinds of posts, and it's ridiculous how many of them there are. Mods can ban the accounts one by one if they're reported, but there's nothing stopping the spammers from creating an unlimited number of them. So how can we stop that, short of requiring a fee for registration? I don't see an easy answer to that.
A lot of people who come to this forum likely don't have Bitcoin though and are looking to learn more about it. These are the people who I don't want to be restricted. Implementing a registration fee would likely prevent the spam we are currently having, but we would also lose users who want to learn about Bitcoin. Not everyone who comes here will even have Bitcoin for the whole time they've registered. That's not because they are into alt accounts but, because they are interested in the technology and like to participate in discussion.
Limit the access to section for new accounts can be a solition but I don't know if this will be a problem for regulars users and for the admin.
To what rank though? If it's something like jr member then they'll just spam elsewhere until they reach that rank. We might find that some people will be lazy and wouldn't do it, but that's when they pay for bumping services. As long as people can make money they'll continue to find ways around it.
I might be optimistic, but I think if we had more people actively reporting in that section we might be able to make it more tolerable.