I love iTunes Match. Makes my barebones home entertainment system shine! Also, it has saved a ton of space on my iPhone, and that of my wife's, which were filling to the brim with photos, etc.
The copyright holder gets paid every time a song is played. The $25 you pay to Apple, to some extent, goes to the record company/artist. Does that make torrents legal? No. Does it make them any less immoral? No.
Why are you pirating music? Is it because you can't afford to pay retail for the music? Is it because the music is not legally available where you live? This is the case for many pirates. These are not potential customers. For them to listen to the music for free is inconsequential to the copyright holder and therefore, in my opinion, totally ok. Enjoy the finer things in life fellas!
If, however, you pirate music because you'd rather spend the money on something harder to steal, to "screw the man", or because you're just too lazy to go buy a CD (or enter a credit card into a digital distribution service), then iTunes Match is not going to save you from the fires of hell.
If you have money for iTunes Match (and a computer / iOS device, and a broadband internet connection to use it), then you don't fit into the first group of pirate, and are therefore a bad person.