In Thailand, a hitman gets paid 2,000 baht for a hit.
i.e., your life may be worth as little as 2,000 baht while you're in Thailand.
In this context, no one has time or money to be worrying about safety in public areas.
If you're inside a hotel or a ticketed tourist site, then yes, there MIGHT be some safety precautions and warning signs, because you have paid money to contract yourself OUT of public Thailand and INTO an 'upper class' zone.
Even in the nicest suburbs of Bangkok, the public areas are still underdeveloped. Step outside your 5 star hotel or gleaming shopping mall... the sight of garbage and cracked concrete, and the smell of sewerage will soon hit your nose. By Thai logic, that's your fault for not arranging a private car to pick you up from the entrance.
It's Thailand, not the west. Each person needs to look out for ourselves. Don't offend locals, especially those who are strong/young/drunk/drugged/crazy. Look where you're walking (3D awareness) and keep your wits about you.