Good that you can get info on breeding rats here, eh?

On a more serious note though, there are major "cultural" differences between breeding reptiles and amphibians vs breeding mammals. The biggest one I figure is in mammal breeding where the mentality is to aim for the best pedigree of show winners from big names where in breeding snakes it's more about the quality of the animal, regardless of who produced it. So if you're a hobby or smaller breeder in the reptile community who consistently puts out nice looking animals, it's easy to build yourself up from that point. Being a generalization it isn't true about all mammal breeders or all reptile breeders, but it seems to be the case most of the time.