Imagine you broke someone's leg. Would you rather kill the person and pay $1000, or spend the rest of your life in prison? Letting the person live and paying them $1000 isn't an option. You either get away scott-free, or ruin your life. I can completely understand a culture in which the reality of the consequences makes people choose the lesser punishment.
The solution isn't to increase the punishment for killing someone on the street. The solution is to abolish the ridiculous costs associated with merely injuring someone, especially if that injury comes from an accident.
Of course what's absolutely a joke is people acting all aghast about another country's culture from behind their white picket fences. You do realize that if you were born in their country, you would have the exact same perspective? What the fuck is with this high and mighty bullshit? Your upbringing in a privileged society doesn't make you better than those from less privileged societies, it just makes you privileged. Be thankful your day-to-day routine doesn't involve having to worry about the possibility of having to kill someone in order to keep your pristine life intact.