The reason that we do it that way in the US is because there was confusion many, many years ago by some flight crews, and one B727 flight crew were arguing about it just prior to hitting the hill near Dulles... It's why now we all say Maintain XXX till XXXXX cleared XXXX approach. It is also why the ATPAC (Air Traffic Procedures Advisory Committee) came into being, because one airline figured out this was being done and told their crews about it, but it wasn't getting to other airlines.
regards
Scott