When I looked at the Signature campaign ANN some hours back, it was over 5 pages of replies and I was wondering what could have attracted so many users to apply so fast only to realized it was accepting Jr member rank as well.
I am more than certain there are some individuals who have woken up their Alternate low ranking accounts in order to participate in that campaign. Maybe it's also a good campaign for low rank members to grab an opportunity and start off a journey here. Time will tell.
There are not many free slots in the campaigns. Probably many people think that $20 is still 20x more than $0
Plus, to be realistic, the power of the Bitcointalk forum is declining, and so is the payment rate for campaigns. Although $20 for Jr. member ranks as quite the correct payment.
For example, just a few months ago, $50 a week on altcoinstalks was considered miserable.