I know there are variables and of course, my reasoning doesn't necessarily apply to all cases but you understand what I mean. Theoretically, you could sell the six offspring for one sixth the cost of the parents + costs to raise the animal to marketable weight (+ box charge, haha). No one would do this of course
Not only would it bring the market price down but it would be down right silly.
But more to the point, it would only take a few sales, possibly even within the same generation, to recoup. Nonetheless there will be a time when you have recovered all you money but still sell the subsequent offspring for the original price. I know exactly what you mean, though.
But I will say this: If I buy a $5000 snake and the breeder charges me $5012, I'm looking elsewhere