No offence intended or inferred but it's a little disingenuous to say it's not that simple and then imply that a simple reason is quashing ego - not that the fact that Russia isn't known to be a humans right bastion of the world should really need to be addressed, here.
You also seemed to have missed the recursive pattern in her statement. "I'll probably be on the streets," infers - to me at least - that she'll be homeless and/or without the prospect of any employability. This facet, right here, explains the recursive nature of repeat offenders.
Approached another way: Was she originally in for theft, which could be a felony, and keeps landing in jail because she can't get a job with a felony on her record and, therefore, has to steal to survive?
Disbarment from employment because of a criminal past is an example of how, even though the debt to society has been paid (e.g.: prison time, fines, etc.), the person is still - punitively punished - until they die.
Now to finally address the Russia question: How do you think the quashing of the ego occurs in there, if - indeed - such action occurs there? Somehow, I highly doubt that discipline is the reductionary answer and that it includes far more unsavoury contributors than simple discipline.
Put another way, a lot of military forces in the world have rigid discipline training but that doesn't mean that the ego is quashed.
Now, having said all of that, the problem is manifestly far more complicated, I do admit, than my simple explanation.
For example, when jails and prisons are run by for-profit corporations and they're only paid per head, then there's - likely - an unnecessary influence in the sense that the city, state, county, what-have-you will need to keep the prison population at a certain level to maintain the business' profit maintained, to continue to retain their services. The for-profit design, in this regard, is such that a reduction in crime (and, as a byproduct, criminals) doesn't bode well for the system.
Is it any wonder, then, that the three-strikes law[s] aren't desinged around three gross offences but one gross offence (e.g.: felony shoplifting) and two minor (misdemeanor) offences?
Then, there's the societal implications of the devaluation and dehumanisation of life in society. Reduction to a simple action is how a person is defined. So, if we do this, then we are implying that this is all the person is - forever. That's it. Paid your debt by serving 30 days for stealing a candy bar? Too bad, still a shoplifter.
I agree that the issue isn't very simple but I think the majority of the corrosion that enters is far more societal-based than anything else.