Clearly, there are some raw emotions being expressed, here. However, emotions don't make for good laws. The negative effects of criminalization cannot be afforded, and there are no gains that can be attributed to that approach, other than assuaging some emotional needs.
Put my questions another way: How many lives have been saved or turned around from imprisoning pot smokers? What is the cost to society of the criminal/justice infrastructure that caused that to happen? Make it easier, and just figure the money costs and forget the social costs.
I'm sorry, but I have not heard a single good reason for keeping pot illegal, not one.