except for sometimes the leaks are official, to test the water.
I do think pirate or ripped copies suck and i can understand the banning issue so perhapse opeth could kindly leak something from the album but make it maybe a section of a song 4 or 5 mins that would be a nice taster.
afterall a copy of the mona lisa or photograph even if it was brilliant is virtually worthless as its not the real item, bootlegged music is the same no real pride of ownership and you jeoperdise a favorite bands chance of obtaining more support from its record company.
however some bands like hawkwind encourage live taping as long its for personal use and doesnt clash with thier official recordings so perhapse opeth could leak a new song recorded at say a rehersal so knowone will make bootlegs from it but we get to hear the song