If your breeding or have over 10 snakes you should really breed feeders. Yes it cost you money to get that set up (I built a 20 bin Rack that cost around $300) but in the long run it is WAY cheaper than buying feeders from a store. I have 10 snakes say I payed $40 a week to feed them thats $160 a month were it only cost me $40 in food every couple of months and Bedding cost next to nothing and water the same. Maybe a total of $60 every couple of months and that is with 8 colonies of 1.3 or 1.4 rats.
Not to mention when the rats get to big I use them as breeder or sell them to people with bigger snakes/or want pet rats. And that goes toward more food/bedding.