Good-Person
Captain Junkie
You're right, but am happy my working doesn't implement any dressing code. Sometime, short trouser and singlet is my easy wear. That's is why I said it's depend on the the type of work or profession. If you're working under AC I don't see any reason to wearing pants and shirts.
I have also noticed that there are certain kinds of jobs that require people to work in a hot weather. Window cleaners, for example, are the kind of people who work in hot weather. It also looks like they are also required to wear shorts as well.