It is partialy your fault because you accepted the responsibility. You could have said no. In the end though you are rsponsible for your own things of course.
It depends on the situation - Mother's trying to take care of children get more leeway, and yes I will try and help them out best that I can. All others who ask you to watch something for them are basically saying, "I have something for you, do you want this?"
Those who ask strangers to watch their belongings are asking for trouble. If you are living in a smaller town this type of crime happens less. You will be ratted out before you make it to the gas station.
Mother's trying to take care of children get more leeway, and yes I will try and help them out best that I can.
All others who ask you to watch something for them are basically saying, "I have something for you, do you want this?"