B.C.
Daycare's aren't allowed to have them b/c it's considered a raming device, but I have one and yes, my kid has fallen off of it, but she's fine. ;)
If you're worried about falls, have you considered putting pea gravel or sand underneath the area? We don't have ours anchored either and it's been fine, even with my rambunctious 2 1/2 and 9 year olds.