Lots of private owners sell venom to labs.
Many people have hots for display animals, much the same as other people keep venomous/poisonous fish and other beasties in aquariums.
The whole world is not exclusively warm and fluffy.
Still. Not the kind of stuff I’d want in my terrariums, and the insurance issues must be interesting (oh, the terrarium broke and Poisonous Pete just got loose). If I ran a lab I’d think I’d want to farm them too, or go to something like a zoo. I’d know just what I was getting.
A tropical fish store out my way once had a blue-ringed octopus for sale.
http://www.thecephalopodpage.org/bluering2.php