I have a huge CD and LP collection (over 30,000 item). Now I buy most of the CDs and LPs from online sources, simply because the stores of today (like HMV) carry such a limited selection I can never find anything interesting. Sure, you want the latest hit CD, they have it. Try to find something more obscure and you can't get it.
I understand why, of course, but look at some of the better stocked stores in Toronto (Grigorian or Sonic Boom, for example) and you'll find they are always busy and not going out of business.