I really cannot understand the purpose of such a member making posts here. I mean they mus have realized that they are not going to get any merit points for future posts and thus will never rank up. Adding too many posts (even if they are shit posts) does take some time. Are they using some sort of bot to post these.
One possibility is that they are still hoping that the merit system will be taken back and then will rank based on the number of posts they made. Or they might be preparing the accounts with potential activity to sell later.