Why claim a bounty once when they can claim it 10 times or 100 times? Abuse of signature campaigns and bounties by multi-accounting has been going on for years here. Merit simply means that these new accounts will not be able to rank up.
Right, but many campaign managers still come across multiple accounts and ban them from participation as a result regardless of rank.
And many campaigns don't. That's the cause of a lot of the problems. All they care about is page impressions for their signatures and bumps for their threads. It is easier to run a bad campaign than a good one.
Higher ranked accounts can make more from their signatures so there were a lot of account farmers building up accounts to sell on mass. That at least is a lot more difficult now and probably does account for a fair bit of the reduction in new account creation.