why do we need speeding laws? - if everyone drove at the speed they like, then some people would be going down the road 35 mph, some at 100 mph, some at 15 mph, and that would create traffic, chaos, and accidents.
why do we have drinking and driving laws? - when we drink, our decision making is dulled, our senses are dulled, and we get sleepier / inhibitionless. also, our concentration gets shot after alcohol.
why do we have a work safe policy? - work safe policies are made to protect employees from danger, and to protect employers from lawsuits.