One of the criteria for whether a patent is valid or not is that it is “non-obvious.” I remember reading about a patent troll who held a patent on a “system for distributing software updates over a computer network.” Which is, forgive the pun, a patently obvious use for a computer network.

People had been talking about buying music and videos online for at least a decade before this guy filed his patents. IANAL (or an engineer) but nothing in the patents seems more detailed than “sell music online, accept money for it, make sure people don’t copy it.” Which boils down to “buy music, but on the computer!” to borrow your phrasing.