That is creepy as fuck.
Maybe, but I suspect Thailand is a more united nation than the US.
And yeah, from European point of view it's quite creepy.
The thing about the USA is that what unites or unifies us is our shared values, not the (worship of) a King.
The whole point of democracy is that free people coming together to support each other can create a government more stable and durable and satisfying than Monarchy. The experiment is ongoing.
(It's also more humane: think about what a mind-fuck it must be to be singled out and told "you're the prince, you're the king". You have no personal freedom at all. Your whole life is regimented and programmed. What are you doing today? Put on this funny dress and sit on this uncomfortable chair for N hours looking stuffed while everybody else rattles around you like so many robots. Oh and by the way, a few determined people are trying to kill you all day every day, and some of them are your own family.)
(Our guys only have to do four or eight years before the mast. Then we chuck 'em. They're always grey and drained afterward but at least they live through it, mostly.)
― Douglas Adams, The Restaurant at the End of the Universe
But I believe it's very important that in Thai schools there are practices, even starting at kindergarten, to teach children to kneel or bow in front of the picture of the king daily. From what I understand children also sing the Thai national anthem at the start of the school day. Every day at 2 moments (09:00 and 17:00) many people stop what they're doing and stand in attention for a second while the national anthem plays on TV, radio in cinemas, etc... So you might understand that reference for the king is a big part of the education system here.
Also, most Thais just don't have the money to travel abroad. And likely also don't see much of other countries on television. News channels on TV might spend 95% of the news on happenings inside the country (e.g. visits of royal family to villages, etc...). As such, many Thais might not be aware that some countries operate very different from the Thai system.