I could also see it backfiring on Disney and decreasing attendance. Folks like my family and I can't afford the extra money to stay on site. For example, on our last trip, we were quoted $4400 to stay at a value resort, tickets and "free" dining. We stayed off site for $2000 less. These days $2000 is a whole lot of money to us.
If WDW gives resort guests more fast passes than folks staying off site, if the folks staying off site can't get fast passes for the popular rides, they may shorten their stay at WDW or maybe not go at all. That would definitely impact Disney!