In my experience it is all wrapped up in Thai's fierce sense of nationality; and also in their constant search for good luck. Photos of the king sit alongside images of Buddha and famous monks; and their offering alters. It would be unlucky for a business or dwelling not to have these images. This factor may apply more to the older generation.
There is also a daily news program which goes out at peak time on the free channel, with news of the family, which is watched by all ages.
It's a good question and another curious but endearing quality of the people. I would be interested to hear an answer from a Thai person.
Since answering this question I have been to the cinema. Before the film started, it was a shock to hear the national anthem while a picture of the king appeared on the big screen. I cannot remember if this had ever happened in a British cinema in my youth and suspect if it happened now there would be a lot of popcorn to clear up under the screen. That everyone stood up is a another indication of Thai people's respectful nature.
It's worth noting that it is a criminal offence to speak poorly of the king, and arrests with 15+ years jail time have been given to people who unwisely diss the monarchy on Facebook, blogs, or other medium. The king usually pardons these individuals. I mention this as a warning to those posting answers; I don't think this is a factor though in the answer to this question.