SURVIVAL OF THE FITTEST

If a person takes control of something without the knowledge of its owner then it is stealing or cheating in general. This is what I understand of this term. Everyone believes this is wrong and we should not do all these things and all but I still do not understand the reason for treating this activity alone as crime. Lets say I have 10rs and somebody steals it. Whose mistake is it? According to each and everyone this is the mistake of the thief and he should be punished. But if I do not have the ability to keep it safe then I am not eligible for the money. This is what I believe. Of course mistake has been done from thief’s end also but it’s ineligible people who are provoking him to steal from them. A person thinks his job is over if he earns some money and he think he is having all the power in the world to use it as and when required but what I believe is to spend even a penny he should have the eligibility to safeguard it otherwise forget that you are the owner of that money, it is just that at that particular moment the money is with you. Anyway this is the place where SURVIVAL OF THE FITTEST is the policy everybody is following so same policy holds good in case of money also.