Disney needs to get rid of this system, or at least supplement it. If someone wants to wait six hours for the ride after they pay their park admission, then they ought to have that chance. Do the boarding groups of fast passes, but at least have the standby option. i know it would suck, but it's better than a family coming to Disney, paying all the money and effort, and then not being able to see a top attraction no matter what they do because their internet connection wasn't fast enough.
Won't work. The number of people trying standby would still greatly exceed what they'd be able to get on the ride in a day. They'd basically have to cut off the standby line mid-morning (since the ride needs a certain down time each night so they can't run it hours past closing). Not to mention the odds that the ride could go down so after waiting on standby for 5 hours you still don't get to ride it that day. Much better to know right up front so you don't waste your day.