While they might not admit it, some people want to know that these criminals are being mistreated. They like the idea, somewhere deep down, of a criminal being forced to wear pink underwear and being fed spoiled food. It's twisted, wrong even. But it's very much American. Like apple pie, or baseball.
And there are people who have been in jail, awaiting trial for years, I think infamously there's one case in Riker's Island that waited 12 years to go to trial. Jails are every thing that is bad about prison made worse by constant flux, no one has to accept that these are the people they will have to spend years with.
Yeah but the tide has turned against him, he got booted out of office (http://www.rawstory.com/2016/11/sheriff-joe-arpaio-booted-fr...).
About the only positive result from this years' election.
It's still a long way from an evidence based drug (law enforcement) policy, but it's definitely a step in the right direction.
In my own experience, police in Oregon and Colorado have started enforcing DUI and public consumption for marijuana rather than possession - and those charges carry higher punishmebts than minor possession used to carry. My neighbor was raided by a swat team last year, fully armed, with emergency support, for alllegedly being over plant count (a municipal court type violation...).
So, things are moving sideways. The people addicted to making perverse profits are predictably not keen to let go.