An algorithm in a Tower Records store in '99 would tell everyone to buy Britney Spears and Limp Bizkit records. It would not suggest say Spacemen 3 or The Magnetic Fields because they don't carry them in their inventory. It will however suggest a poor alternative that meets some 'nearest-neighbours' cluster threshold in a statistical model.

Independent video stores are not so tightly tied to one distributor, so yes, a clerk that takes a few moments to hear what movies you like could point you in the right direction....even if that direction is to go a different store entirely.