Legal question about Antique vehicles and the seat belt laws

What about all the people that ride a motorcycle here without a helmet( me included) and then you see all the people riding down the sidewalk on a bicycle with one on!!
Have seen people riding motorcycles, no shirt, shorts, flipflops, no helmet.
Also I'm not sure (what I was told) "white lineing" is legal in Florida. Almost got a few, because of that.