That really is not the case down here. There is a 5 ft lane on the asphalt for a bike lane, and then there is the cement curb and gutter that extends another 10-15 in or so to the side of the road where the debris gets swept into. If you keep your bike in the lane on the asphalt, then there is no problems to which you are referring (as a recreational rider, I can attest that these lanes are safe to use even at speed). They actually designed these lanes pretty well, and there is no reason for people to not use them. Those who don't use them are usually the ones who have the $5K+ bike, spandexed out, Lance Armstrong looking people who think they own the road when they are out. It is really annoying.