And I think you're making the implicit assumption here that people who are the victims of petty theft just had their stuff stolen, and weren't assaulted, brutal

And I think you're making the implicit assumption here that people who are the victims of petty theft just had their stuff stolen, and weren't assaulted, brutalized, terrified, or otherwise demeaned in a way that will change how they function or view their lives in society. There's a larger "cost" to petty theft than just the stuff that gets stolen. The reason we have laws, and punishment associated with breaking those laws, around petty theft isn't just about incentivizing would-be thieves to not do it.