I agree with quote, Thais don't really like foreigners but tolerate them. When one kills Thais, they lose tolerance, understandably.
I worked with a guy who killed a motorcyclist when drunk; he paid his way out but was fired immediately.
Another Ozzie I worked with killed his Thai gf with an axe and threw her off a high balcony, allegedly. A few days after being arrested, you couldn't recognizer him. Imagine if an African(for example) came to the UK and killed a young girl, there would be a similar reaction. No one like outsiders killing their own.