I don't think it's something that people would exactly flock to, so much as a small niche market. For example, I occasinally daydream about breeding those european rat snakes E. longissima. And in a few years I'll be in the market for a cb aru scrub, and I have never seen that locality captive bred.
The main catches, is I don't think there's all too much money in it, and you may have to acclimate your initial breeding stock to captivity, but if there's a type of unusual snake that's rarely cb, but somethimes imported that you're quite fond of, that'd probably be the thing to go for.
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0.2 chickens (Falcon & Condor)
0.2 dog mutts (half ownership, only mine when they misbehave, Lucy & Amy)
0.1 Halflinger horse (Crissy)
0.0 Arizona Mountain Kingsnake (coming soon)
1.1 parents
Still searching for 1.0 WC human