It is a very interesting thread. If you do not get replied in 2-3 days , you just forget what or where you have registered for 
THis is too unprofessional ,if you want to get and acquire new partners, you have to reply within 24-48 hours or at least to start a correspondence.
Maybe some of the Affiliate managers are for a short period of time in the casino or bookies, and they are too into numbers and KPI's
If they never reach out, this is not serious at all. The game/ business we play in is for and about humanity and human relations , not to ignore people, delete their emails and pretend that you are number 1 with the existing base of affiliates you are having.
Seven times fall, eight times stand.