Not sure if the sign is there, the place has changed owners, a few times over the years. I'll look soon.
A new rule will be implemented soon, I expect there will be a 10-15 ad maximum limit, in the future. The free classifieds was intended for members, not dealers.
In my opinion, a "Contributing Member", is anyone who offers help to the other members.
Offering parts, is a valuable contribution to those in need. It is very usefull to the members to be able to come to this site and post your project or current needs and know that thousands of like minded people will be here to read and offer suggestions, ideas and parts.
Unfortunately. as the rules state currently(Chris and Mikes decision), you can not post "want ads" or "for sale items" in the Forums. This makes it a little more difficult to get the help, or parts you need, depending on your journalism skills. It is OK to post needs in a thread that has some discussion of your project. (sorry to confuse you!)
Some vendors are very helpfull, others simply sell. It's a tough call how to handle all this...