For the action of taking other people things without permission its consider stealing, hence downloading music, movie from internet without paying is stealing too. But how the heavy of this negative karma action is depend on our motivation, action and how we rejoice it. So this can be very minor if we have a good motivation ie to sharing people who need.
In everyday, we conduct many actions which is combine with good and negative actions, so i will say that if we did 20 good great things and one minor bad thing so that should be 'alright'. As long as we are aware of what we are doing, have a right motivation and don't do it to harm other.
In reality, I think it quite difficult to not have any negative acitons in our daily activities as we are not stay in the cave alone, how many people we meet up and have the interaction with so how many people we have upset them, we angry with them, we use harsh speech, lie etc.. I mean if any of us can do it the best then do and i don't encourage people to just don't care about the minor negative action but since we could not avoid it then we should try to control ourself and make all those negative actions to be lessen and how to have a good habitual which benefit other more that will be better than worry about this right??