Dark skin shows your class, people work outside are low class, and people who do not have to toil under the sun are higher class. When it comes to helmets it is a matter of either cost, low income cannot afford, or I am never going to have an accident why do I need a helmet, and I only ever travel in town at low speed, or I am young and don't care. When the helmet law was introduced in the UK there was a large number of protesters, who did not see why they should be forced to wear a helmet when they did not want to. The same happened with seat belts., only strict enforcement made people comply with the law. Thailand does not enforce its laws except when an edict from on high is given and that soon peters out.