(1) Why would the state residents vote for a state legislature that takes away human rights from them?
(2) And if this is seen as a real danger, can it not happen as well on the federal level then? The whole US of A voters voting for representatives that take away human rights on the federal level.
At the federal level, the https://en.wikipedia.org/wiki/Convention_on_the_Rights_of_th... is an example of a right that has never yet been implemented, partly because some states insisted on retaining the death penalty for children.
A lot of voters wouldn't have a problem if they're going to take rights away from those "other people" they don't like.
(a) That assumes they get to vote: see voter suppression.
(b) Plenty of folks vote for things that are against their own interests:
> Working-class Americans who voted for Donald J. Trump continue to approve of him as president, even though he supported a health care bill that would disproportionately hurt them.
* https://www.nytimes.com/2017/04/12/upshot/why-americans-vote...
* https://www.theguardian.com/society/2012/jun/05/why-working-...
* https://thehill.com/opinion/james-carville/227350-james-carv...
2) This also happens, but it's a bit harder because you need a wider variety of people to agree, and federal-level politics get a lot more visibility in the news.
Consider that referenda are generally uncommon and that you have to vote for a whole politician, not individual policies.