The time and effort were already expended. You can't steal those anymore than you can "steal" a digital file you made a copy of. If I build an app and sell it

The time and effort were already expended. You can't steal those anymore than you can "steal" a digital file you made a copy of. If I build an app and sell it for a $1 and someone purchases it for that amount and then makes a copy for his friend I have simply missed out on revenue, but my time wasn't stolen nor was my app.