Addiction is a mental illness.  I still hate junkies because they steal even from other poor people, they hoard shit and are dirty so entire apartment buildings get bedbugs, they are loud and they often smell awful. I still hated on my neighbour (who lived right across from my place) with untreated mental illness who would yell and scream and keep her door wide open while sitting down with her unbathed, mostly unclothed obese body on full display for anyone walking down the hallway to see.