Back in the 1980s - "Home Taping is Killing Music". It was illegal then to hold a backup copy as far as the BPI were concerned, never mind hold a bootleg LP of a gig ( *cough* ), luckily the law had a different view. The idea of downloading music and then going out and buying is fine by me.
As for SACD, in fact, this applies to any disc, the more care taken over the mastering and engineering of the disc, the better it will sound. Being on SACD is no guarantee of anything if the production process was a duffer and moreso the mastering.
If you want to hear a good SACD, snag yourself a copy of Mark Knopfler's Shangri-La - stunning. Really shows off what the format can do. Where SACD fell down was the manufacturers and labels failing to work together to produce something the listening public could really get a hold of and understand what it was all about. Had SACD had half as much of the marketing effort DVD originally had with a steady stream of titles coming from the record companies, it'd have been a roaring success.
As it is, we have CD - it too can be excellent and will be a dominant format for a while to come. As has already been said, people like to hold on to a physical product, hence why I still buy vinyl and CD. Downloading has a place, but barely scratches the surface for me (I think maybe 50 tracks to date?). Give me Wolfgang's Vault anyday! That's a far more interesting proposition!