I will gladly answer this question for you as my family has asked me the exact same question a billion times.
Firstly, why own a snake of any kind? This is the root of my family's issues with many of my pets. "They can't bond with you or recognize you, whats the point?" So if you think snakes are ok, but hot snakes are not, then I ask you the same question above....why would one be ok and not the other? Yes it is more dangerous, but so what? And not ALL venomous snakes can kill you...
For me, personally, I like to own snakes (and tarantulas, scorpions, and what have you) NOT because I like to display them but because I absolutely love animals. I genuinely study them. I don't breed my animals, and in the rare case I would attempt a breeding it would be to understand the processes the animals go through, not to make certain genetic babies. I try to understand why they act the way they do; what their behaviors mean; and whatnot. I don't see why any venomous animal is different in any way?
Do you feel the same way about tarantulas? scorpions? or really any other non-bonding non-display animal?