[alive2007]

People often use this very semantic, very pedantic difference and expand it to make it a difference in practical effect. Piracy and theft have the same practical effect : you're accessing a consumable good without paying the requisite cost, your individual crime may not have a large effect on the ability of the seller to provide for that good, but, on the large scale, if everyone committed your crime, you would severely affect the seller's ability to both 1. provide for him/her/their-self and 2. provide that good to the people. So, for all intents and purposes, yes, piracy is theft.