Not everyone has to be a saint to be part of society. There are plenty of people that wouldn't be in a life of petty crime if they had better options. The fact that we have more train thieves than say any other given country is more to do with our lack of opportunities for these people than the fact that we aren't disincentivizing it enough. Plenty of places that have fewer disincentives for crime yet have less crime. Disincentives can work as a brute force method, but if there is an underlying reason why certain minorities or groups of people are inclined to what we have defined as a crime in society, then brute force methods will just push them toward alternatives, and it may not necessarily be finding a good 9-5 job as you suggest.