Another point is that breeding has costs that simply keeping doesn't. Equipment such as incubator + high quality thermostat, thermometer, and hygrometer, hatchling rack + thermostat, accessories like hides and water bowls, etc. will set you back a few hundred even if you find quality stuff locally.
Also you really need a good exotics vet that can see your prolapsed male or egg-bound female with little or no notice, and obviously some cash in the bank (or room on the credit card) so that getting your animal seen immediately on an emergency call doesn't mean you're eating Ramen for the next month and figuring out how to pay the rent.