The issue with pet store prices is that the bottom line is they are in business to make money, so they will mark up as much as they can. If they have balls selling for $75 they will keep that price, or raise it to see if they can get $89. Thats their business.
Also you have to realize that most people selling snakes they breed are not making a profit. Big time breeders are, but small guys are most likely losing money if you factor in the amount of time spent caring for their animals. I easily spend 2 - 3 hours, 4 nites a week with my snakes. Add to that the cost of heating them and feeding and I'm probably behind the eightball. But its something I enjoy.
Now, your corn snake. You said you are considering trading it back for a hatchling. If the snake you have is bigger then a hatchling now...it was feeding on something. try different ways of feeding, live, frozen thawed. Hatchling colubrids do well being placed in a separate small dark container when fed.
Once feeding, your snake will be as good of a breeder as any other. Many snakes are tough to start feeding, but once started you'd never know there was a problem.
Good luck!!

-----
"The band is just fantastic, that is really what I think. Oh by the way, which ones pink?"