Handicap access at Disney varied by ride when we went. For some rides, there were special transports that prioritized them. For example, there were two trucks out of the many at the Safari that had slots to park wheelchairs and scooters, so people who needed them waited for those trucks but got right on them when they arrived. For those who could transfer to a regular seat (like my wife who had a knee problem at the time), they let us in a side entrance and would seat the group (with assistance if needed) in the regular trucks. That's the sort of thing that this scam was taking advantage of, where someone in the group would pretend to need a chair/scooter but be "transfer capable" so they'd get bumped up. Some rides just didn't handle chairs at all, like most of the rollercoasters, but we still got passed around the line at times because she could move herself from the scooter, she just couldn't stand in the line.