I would go to the airport and play dumb (tell them you only saw it the night before as you were checking your ticket). If you go to immigration then you're admitting to breaking the law, and like in any country there's a good chance they'll detain you and hold you until you're deported.

While if you're at the airport and pretend you misunderstood the rules (which probably happens a lot), and you're leaving anyway, it's way easier for them to fine you and send you on your way than to detain you and deal with all that paperwork. Especially now that they want to attract tourists they don't want to make a scene either. Just look scared and upset, if it's your first time they'll probably let you off easy.

@Alexander ****

from what I've read different banks and even different branches will have wildly different policies. I suspect it's more a matter of not wanting rather than not being able to help, and you might get lucky if you keep trying. Then again this was information from before the pandemic, maybe things have changed now but I doubt that.

That is correct. To get a tax ID last I heard they advise to open a local bank account which will give you one automatically. Thailand elite visa includes a bank account.

Once you do and you spend 180 days per year in Thailand, you qualify as tax resident, which means you don't pay any taxes on income from a foreign source. From what I've read this isn't a foreign vs local sourced distinction as in most other countries (as in in which country were you when you worked for that money), but rather if the money enters Thailand or not, which is a huge advantage (most other countries with territorial tax systems do tax locally sourced income, even if it doesn't enter the country).

The bigger issue is your country of origin and the country were you earned that income, because both will be interested to tax you. Many countries have some unclear rules you need to comply with before they consider you as having moved to another country (which can be having a long term residency permit, spending minimum 2 to 5 years in said country, not having any attachments in your country of origin...).