I appreciate the helpful comment. I saw a post awhile ago about someone talking about how participating in a signature bounty lowers the chances of earning merit because it shows that the user wants to do bounties, rather than providing value to the forum or something like that.
There are some who prefer to give merits to signatureless members. They think that by being signatureless, that member's intention is not to make bitcointalk a money-making site but to really learn and contribute to the community (this attitude is highly encouraged which gives that signatureless member a thumbs-up).
Many will scrutinize your post first if it deserves a merit then look at your post history if you are a spammer/shitposter then they will analyze your intention and decide if they will give you a merit or not. (Hence, the merit that you will get does not depend on just your current post but also on your previous posts)
However, most of the members do not associate signature campaign and giving merits. They just look at your post and then decide if it is merit-worthy or not.