CJ (and other networks) love it because they make money off each transaction. Merchants should love it for the reasons you cited but many have a different attitude.

In short, there is a lot of opportunity in this game for affiliates as long as they put in the time and effort it takes to get good at it. The market place has been quite competitive for years. I regard this to be a sustainable modle. I think it will be going strong for the forseeable future.

I'm sure it is possible to make some short term profits buying traffic and sending it directly to affiliate program landing pages, but there is no long term value being built.

Seems like a lot of work to buy traffic and hope it converts while also hoping that other people don't increase the bid amount necessary to get the traffic. Seems like a tough game that has no prospect for long term sustainable success.

Companies like CJ and their affiliate programs must love it because most of the testing, risk, and expense is taken on by people who are gambling that they can win the PPC game.