Your image vague and better be removed.
What strategy do gambling developers to expand their market to countries which do not allow any type of gambling?
Do they continue with allowing users to use VPN, or do they have "some trick"?
I ask the question because curious many gambling sites operated in "that country" look to exist and are very developed with a big profit of billion of dollars.
I don't know exactly, I had a bad thing on my mind, they are bribing government officials and Police in order to keep operating, This is my assumption only, maybe you are here and can tell the truth.
You've just answered your question. If an online casino isn't allowed to a country that you're asking then that's for sure that users from that location are using VPN.
Some casinos allow it and many that don't.
As long as the use of VPN is just for accessing it then there's no issue to that casino as long as they are allowing it.