I think that as more people talk about it, more children will be RF longer or in a 5 pt harness longer. It only seems odd because it's new. Our Britax goes to 65lbs FF and 35 RF. DD sits cross legged in the back. She's over 3. Kids work it out. I would rather she have a broken leg than a broken neck. One of my own friends got very upset when I stated it was safer to put DD RF longer so she'll stay til the limits of her seat. It's not a personal attack or a scare tactic. Statistically speaking, she is safer that way and that is my choice. I see no harm in discussing safer options for our children, like not putting them in heavy coats or snowsuits or buntings that the straps go through - not unless you want the suit to stay in the car and your child to be thrown from it.
http://babyproducts.about.com/od/carseats/a/carseatcoat.htm
I don't post my kid's pictures online, but I'm sure a little googling will find children over 2 RF with their legs crossed or otherwise arranged so they can sit RF.
Here's a 4 yr old:
http://babyproducts.about.com/od/carseats/ig/Extended-Rea...
Here's a 4.5 yr old just chillin' with her leg over the side:
http://babyproducts.about.com/od/carseats/ig/Extended-Rea...
My car is a Saturn SL1, so not huge. And we have a Marathon.