First part
It is an interesting idea arising in some european cities, that traffic rules actually go against their intention.
Controlled Chaos: European Cities Do Away with Traffic Signs:
http://www.spiegel.de/international/spiegel/0,1518,448747,00.htmlIt may sound like chaos, but it's only the lesson drawn from one of the insights of traffic psychology: Drivers will force the accelerator down ruthlessly only in situations where everything has been fully regulated. Where the situation is unclear, they're forced to drive more carefully and cautiously...
And some people already discussed it...
http://www.freerepublic.com/focus/f-news/1741329/postsMy take on this: it would work differently according to the culture of the region where it was implemented. In some cities it would mean absolute chaos, it others it wouldn't.
Second Part
Now expanding the horizons, the existence of laws does not change personal moral and ethical values.
"I don't kill because it is forbidden and/or because I'll get killed/arrested for doing it" instead of "I don't kill because it's wrong" or
"I don't kill because mutual aid and cooperation is better than competition and brutality"Although it may not seem, that statement is in many cases true. Law can limit the actions of someone, but change one's will of doing wrong things.
Of course there are exceptions to the statement "killing is wrong" like killing a serial killer that is rushing against you among other cases.
In my opinion it's quite simple:
The existence of rules is the first sign to identify what isn't an utopia
The less rules become necessary, more closer mankind will be to an ideal world and society.
Lastly a quotation from a certain book:
"The silly sentimentalists of the French Revolution talked about the Rights of Man! We hate rights and we hate wrongs. We have abolished right and wrong."