Yes, in my opinion is very important to know if they are locally bred or imported from Brazil. Knowing that is imported and still buying them i would say your are more to the side of contributing to the extinction than making any good to the species ... always be aware of that, that's what i call being a responsible fish keeper.
Ofc most will buy them, they are rare and beautiful and if you dont buy another will, but i think it is important to know why a specie disappears and people wonder what happened to them... and after that not even the richest fish keeper on the earth will bring them back with any amount of money, same money they used to contribute to their extinction.
It is important to remember that most fish keepers can't keep a fish for a few years, they are compulsive, they overcrowd their fish tank with fishes that end up dying because of poor water conditions or eating each other... or when the fish keeper gets tired and sell all fish to house different species...
The best place for fish in extinction is in their natural habitat, not in our tanks.