Merits received for the bounty in my opinion are not entirely honest. People give their manager a sign of appreciation that the campaign was successful, but this violates the very essence of the merit system. Initially, it was aimed but that would stimulate people to create high-quality content, and eventually becomes a sort of forum token.
Literally campaign managers don't need much of merit because they are not kind of being after it, but a sign of appreciation can be a good sign in order for other user distinguish that the campaign manager handles smooth, but not always to prefer merit about it. Trust should be given instead of merit, However it is the givers decision, the only problem is abusing it.
I agree that the sender will dispose of his merits as necessary. However, the rules of the forum clearly spelled out what merits are and how the system works as a whole. If users will use merits absolutely without control, then the system will turn into a forum token, which will be used as a local currency.