"because I don't want to deal with their installer or give away my billing info"
Of course - because once they have your billing info, they can actually bill you and your bank account will decrease by the cost of the CD.
So you pretty much proved his point - you just don't want to pay for something you can steal.
The word for this is "tragedy of the commons". http://en.wikipedia.org/wiki/Tragedy_of_the_commons
As for convenience, I may find it more convenient to download music from TPB or a college FTP than from iTunes, because I don't want to deal with their installer or give away my billing info. Convenience is an utterly subjective measure.
(also, your car analogy is shitty and bad and you should feel shitty and bad)