I have only asked if there are any special needs, is this wrong?
You didn't just ask, you said that you actually started posting on certain boards, presumably to improve your chances to get accepted into the campaign.
Are they posting there because they like it? Of course not? Are they signature spammers? In my opinion, only if their posts are spam and any other reasons shouldn't be important for a moderator.
I can quote here multiple comments from members who are complaining that they have to write in some special sections only because of the signature, why nobody targets them?
I don't know what else I can tell you other than "agree to disagree". If you don't see anything wrong with this then I don't think I have any arguments to affect your opinion.