I actually rented an X5 in Florida from Avis. You would have to boil it down to BMW wanting the cars to get into more dirvers hands. I often look for cars that I might buy at the rental location so I can really test it out. Of course, how they're optioned will influence people's view of the car. Knowing the rental companies, they got a good deal on these to stick them into their fleet.
2012 535xi M-Sport, Carbon Black, Cinnamon-Alum Hex, Exec Pack, Tech Pack, HUD, Damper Control, BMW Apps, Heated Rear Seats