I think not even selling products. Some websites earn from microcredit. Like, for example, the website offers to remove 3 unwanted items from your picture and then pay today only 0,7 $ and enjoy the service for 7 days with 50 % discounts means 0,35 $, and if not satisfied you do not renew and offers such AI services, and then offers to renew for 7 days for original price that is 0,7 $ and 50 % discount as welcome bonus then back to original price or for one month for 3 $ but as a new user you get 50 % for 1.5 $ or for one year for 36,50 $ but as a new user you get discount of 50 %. Then you find yourself when subscribing near to end a discount between 20 % and 35 %. Such subscriptions on AI services bring money better than Google Adwords itself.