Remember Napster? It was only good for people who listened to mainstream chart toppers with crappy sound quality. It was not an option for people really interested in music.
The Pirate Bay is today's equivalent of Napster for music (discounting things like LimeWire of course, which are only used by the real filesharing noobs to trade terrible quality tracks). Most of the music torrents (at least the ones I have seen) are encoded about about LAME V3 or V4 (or equivalent), which isn't crappy, but nor is it audiophile quality. The Pirate Bay does have a Flac section, but the selection of music there just isn't comprehensive enough yet.
Anyone really interested in music should be on one of the music oriented private sites (such as OiNK was back in the day) where the rules about quality, completeness etc. are much more draconian. Tried finding a really small band on TPB recently? A search for "Tall Firs" on TPB finds nothing, but on a private site, two albums in a multitude of different formats/qualities are returned.
The pirate bay isn't an option for people really interested in music