system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why does the Empire use slave labor?

Yes they are supposed to be the bad guys, so saying they use slaves makes them sound really evil. But how practical is it to use slaves when droids are so easy to produce? They must have reached the point where it is cheaper and easier to just automate. Slaves even if poorly treated still need food and shelter provided. Add they need guards as well. 

Some sources mention using Wookies as slaves on the Death Star construction, isn't that suicidal? Wookies are very temperamental with insane amounts of strength.  and the chances of an uprising would be high. You would need a guard for every Wookie slave. 

Why not make huge droids just for construction, they would not need to be humanoid in shape. Imagine being octopus like in shape. They would be able to life heavy loads and move wherever they are needed, and could work in a vacuum.
gpt
Simply put, it’s another form of enforcing control over the greater galaxy. While slave labor is typically economically inefficient (rebellions, housing, etcetera) the psychological impact it can have on the average citizen is enormous. Sure, life may be less tolerable under the imperial yoke than it was before, but is it really worth rebelling when the consequences may not just be death, but the enslavement of your family and possibly your entire species?