It's a list of groups of people who are traditionally ignored by most companies, but are hired by this one. If Harvard grads were traditionally unemployable, but employed by this bakery, they would also be on the list along with felons, immigrants and addicts.
I think you have your ranking backwards. Having committed a crime means you screwed up. Being an addict means a life-destroying drive that never truly goes away.
Because that same lack of empathy for other people, together with a lack of self control also affects other parts of their life. If that's the kind of person they are then people have a right to now that and judge them for it, because they are likely to do it again.
It doesn't mean never hire them, but it does mean don't put them in a position where they have a larger ability to hurt others.
Obviously some crimes are of the "stupid teen" variety, and other motivations - those should be categorized differently.