If I get you correctly what you mean is that individual company contacts a member of the forum by making him her a special offer to wear their signatures, that is nit so popular here in the forum, but I am sure we still have some members of the forum who have special offers to wear a signatures without any public signatures campaign to employ multiple others.
What is popular here in the forum is signatures campaign and it is under the manager who make the pay foll and the pay day and he is the representative between the company and the members.
It must've been a big honor for companies to contact members privately to wear there signatures, that must be in the early days when the number of forum members were not this much, I guess some pioneering members will still get the preferential treatments. What I met on ground is joining a signature campaign, through a campaign manager, and I think it makes the relationship between the campaign perticipants in the forum and the company they're advertising for to have cordial relationships.