The Thai hospitality workers are not in it for the hobby. They are working to make money, support their families, and appreciate tipping as part of their compensation. I have been visiting Thailand for years and have many friends that work in hospitality and have told me so. I have dined with Thai friends who also tipped and there was nothing strange about it. Tipping is not mandatory but if you like the service and want to appreciate the worker then go a head - if you don't want to, then don't tip. No one if forcing you to tip.

I remember dining at informal pizza places at Rome's Trastevere (delicious pizza but lousy service) and 10% "coperta" was tacked onto my bill at every joint regardless if I liked the service or not. The same in many other European countries, it is automatically calculated in the final tally and you have to pay it. There is no such a thing in the USA, 15-20% is encouraged but never mandatory. You can leave a penny or nothing and no one will even bother. So, this is not the proper thread to spume your anti-American rhetoric and please take your arguments to OMNI.