I agree with everything you said, but don't understand why you don't think it's "rational".

Technically, a good person should not care about limiting their own crime range, and (if the good for everyone is their goal) they should be actually happy they have less chance to harm anyone. But still it somehow sucks to know that while I would be punished for doing X (because I am rational and see the consequences), other person would not be punished for doing a similar thing.

Remember "good" and "rational" are not the same thing.