I would not have bought it anyway so its ok to copy
This is an interesting, but dangerous, heter that people use. This gets into the whole hock about the fact that you are not stealing an actual physical object, but rather intellectual property. So since you wouldn’t have bought it anyway, the producer is not “losing” anything by you copying it.
The problem is, how do you determine that you “wouldn’t have bought it anyway”?
What if you had no music and this was all that’s available, would you buy it? If the underlying reason why you “wouldn’t buy it” is because you have so much (stolen) music already, so you have no need to pay $15 for a CD, then according to that lamdus, you would never pay for any music.
Let’s say you are currently a poor Yeshiva bachur, but 5 years from now you get a job and can afford to buy some music, will you then go and pay for some (or all) of the music you stole 5 years ago?
They are selling the CD for $15 which you won’t pay, but would you pay $0.99 for one song if it was available individually? If so, then perhaps you are stealing because you would have paid $0.99. What if a year from now the price will drop from $15 to $10, and you are willing to pay $10, would you then go and buy it, or once it’s stolen it’s stolen and you feel no achrayus to buy it?
All of these are important questions that if answered in certain ways could mean that you are actually stealing even according to the “I wouldn’t have bought it anyway” heter.
Kol kula tzricha b’dika…