This thread is confusing... I havn't biked since I was a kid but I learned how to bike on a sidewalk. We also solely rode our bikes on sidewalks, did not need to register, and didn't follow the speedlimit. We didn't stop at stop signs or anything like that. I thought those were all things you follow if you were using your bike as a car (driving in a lane, etc)?
Is there a point in your life when your bike turns into a car and you need a license plate, have to register, need a front light, must be wearing a helmet, can't ride on sidewalks, must stop for stop signs no matter where you are, can't bike in a parking lot, and can't bike too fast? If so, I'm glad I stopped while I was ahead.