Thailand tries really hard to appear as though it is a vacation area for people seeking sand and sun and for a lot of people it is precisely that. On the other hand though, you don't need to be here very long before you realize that a lot of people travel here for the nightlife that can get pretty crazy. It's a little too crazy if you ask me.
I'm not the kind of person that likes to be out drinking until the sun comes out the next day and the few times that I have done that in my life I have, like most people, regretted doing that for days after the fact and even remember some of my legendary hangovers that happened years ago as if it was yesterday.
While not so much of a thing here in Chiang Mai, a lot of the rest of the country has nightlife that just never seems to end.
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Even though there are very few officials that will admit it, a lot of the nightlife in this country is geared towards the world's oldest profession and there are some hotspots where this is almost immediately evident. Soi Cowboy, Patpong, and Nana Plaza - which are all in Bangkok - are some of the more well-known ones. The entire beach area of Pattaya is another one that is so over the top that it just seems gross to me is the same. In Phuket it is a little more sedate, but if you ever go to the famous Bangkla road it won't take you very long to figure out what it is that this area is mostly in the trade of.
Thai nightlife for the most part is something that is determined by local officials. There actually ARE nationwide laws on operating hours but from my experience it seems as though the application of these laws is decided by individual areas of whatever city they happen to be in. Just like prostitution, staying open past midnight is technically illegal but if the local authorities aren't going to bust anyone for it, or if they are actively paying the police for the "right" to stay open past those hours, who is actually going to bust anyone for it?
Even my local pub, which doesn't feature any ladies of the night stays open until they feel like closing and they are on the same major road as the police station. Nobody cares as long as you aren't making problems. When I was speaking to the owner one day he told me that he pays the police a monthly amount and they advise him on days when he has to obey the law because a "higher-up" is going to be doing an inspection. Other than those days, his bar / restaurant just gets to stay open as long as they feel like it provided they do not make a problem for the nearby residential areas.
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you only need to go here once and it will amaze you with how basically everything that goes on inside here is obviously against the law - but nobody does anything about it
There is a new government bill be proposed that would make the operating hours of pubs nationwide be extended to 4am and I think this is a bad idea for a couple of reasons. For one thing, there already are bars that stay open until this time due to paying off the correct authorities and another thing: Do you really need to be out drinking until 4am?
Maybe I am just a bit of a prude but other than making money for the bars, I can't really think of any particular good that this would do for society at large. Thailand is a massively corrupt country though and perhaps this ruling would eliminate the leg up that larger, richer businesses have over their competitors. I doubt it because the local police just seem to make up whatever rules they happen to want in order to make as much money for themselves as possible.
For me i think that if you are going to move the opening hours to such an ungodly time of night you may as well just let them be open 24-hours a day.