Strollers are supposed to be folded when on the bus. Most people don't, I don't mind as long as your child isn't in it and the brakes are on and you move it out of the way as much as possible. It irritates me when a parent has a kid in stroller and refuses to take the kid out. I usually say, "If I crash, you're gonna trust a stroller... WITH wheels to keep your child safe?"

The bike thing is policy, no way around it unless your bike folds. I have a few passengers with folders.