Oh right, I forgot, the $1 incentive gives people an ulterior motive for signing. :/ OK, so this is part of the answer to my original question—I had not noticed that fact and thus overestimated their usefulness.
Oh right, I forgot, the $1 incentive gives people an ulterior motive for signing. :/ OK, so this is part of the answer to my original question—I had not noticed that fact and thus overestimated their usefulness.