I don't think bounty threads should receive any merit, In fact it is better to divorce merit from bounty promotions. Of course if a bounty poster makes a good post, then he should receive merit, but not if it is about bounties or other spammers topics.
I have observed that some people merit ANN threads (I did it once, 1 merit). I think that it could be the natural thing to do to give a small award to the manager, unfortunately it has been abused over the first months of the merit systems, but I also believe it will be back to normal.