Here in our country gambling is illegal, but online gambling isn't, due to the reason I mentioned above. There is actually a 'gap' on the law that allow that interpretation by regulators. So technically the same interpretation should be valid for a casino business owner.
In some countries, gambling is totally illegal, be it online or offline casinos. You can take note of that in countries like China and Muslim countries.
Even you don't have a real-office, "CURACAO" are still gonna to give a license for every online-casino who are register to them as long paid the money ~XD. That's why, I never look a casino by the license.
I look the casino by the testimony and review from some user.
That is true. But it is good to start from the gambling site license, but that does not mean, once a casino has a good review by people and being popular, that is enough to know that such casino is good enough for someone to register. But as for me, I check all. I check the licence, customers review and also the ToS before I join any casino.