The day disney says I can only ride their rides once per day will be the day they stop getting my money.
I don't think Disney will ever blatantly draw that line in the sand but as I said in a previous post, I do think there is some desire on their part to level the playing field. Previously, guests who are most knowledgable about the parks are bound to have the best experience. Those who know when TSM FPs will run out...those who understand lines are lower early in the day....those who know better than to get a FP for Indiana Jones or Mickey's Philharmagic.
Every day there are thousands of uneducated guests who enter the parks and find themselves unable to ride TSM, Soarin, Test Track and others without a 60+ minute standby wait. Or, during peak seasons, they find they can only experience a handful of attractions...all with long wait times or distant FP return times.
In its current iteration, FP+ seems like a way to allow every guest to lock-in certain attractions before arrival. It virtually eliminates the possibility that a guest walks away, thinking "the only ride my kids wanted to do was Dumbo but the line was just too long."
We could probably argue that the old system was "fairer" in many respects, but this new system does make many attractions more accessible to the masses.
Yes, Disney does risk losing dollars from some customers if they find the new FP+ is not to their liking. But for years, Disney has already been losing money to the people who pledged never to return after experiencing long wait times and exhausted FP supplies.
I agree with another poster that the best system may be a combination of advance reservations and same-day FPs. We'll have to find out if Disney agrees.