CF money though it may not make as much money, it's more 'consistent' and slightly less vulnerable.
Pop Banking relies heavily on either someone producing food for you or on the market. if you're relying on food from the market is at about 0.25-0.4 you're not making much money then are you, because you're spending anywhere from 1/3-1/2 of the money your making on food.
With pop banking, you're also going to want to 'maximize' production, so you're not going to want to build research centres, as they're interfere with your to %. However, you still want that tasty econ bonus, so you'll be investing X amount of money into your research, most people do about 2-4 ticks of their daily income.
Plus, you're highly vulnerable to ops, such as hypnotize and e storms as well as nukes. That will destroy your pop base and ruin your income. Whereas, CF baking is only vulnerable to nukes.
So, in reality, though you may be making more money, you're also spending more. Since you're a banker, it's your bottom line that counts. So, With CF banking you're not worried about any building percentages, so you can build RC's and Hydro's for some food. Since, you're not spending your money on anything, your bottom line is larger than pop banking.
Kadaj
Death is not to be mourned
It's meant to be savored