My first job was at a pet store that offered all kinds of snakes. Cal Kings, Desert Kings, generic red-tails, albino burms, norm/amel/snow corns, and balls all sold as fast as we could get them.
tricolor kings/milks, trans pecos rats, bairds rats, garters, amazon tree boas, kenyan sand boas, and florida kings just sat forever with practically zero interest in them.
I had a lot of conversations with the owners about why this was, but nobody could figure it out. most of the time the babies were priced roughly the same and the care was still easy... people just had zero interest in them. My guess is that many first time snake buyers are inclined to go with species they've heard of before rather than something they just became aware of.
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1.1 Argentine Boas
1.1 Dumerils Boas
1.1 Black Milk Snakes
2.3 California King Snakes
1.1 Nelsons Milk Snakes
2.2 Corn Snakes