There are a lot of legal reasons why online gambling is legal.

First of all, online casinos aren't places where people gamble for real money, rather , they are virtual sites where people get involved in activities in the same fashion as traditional tables and slots do. If the activity is free, then so is the law.
This is the reason the majority of online casinos have been operated in the same way as casinos offline.

With online gambling, though, you do not need to leave your home, so long as you have access to a computer. All you need is a computer, an internet connection and a credit card. You may put a simple wager on the slot machines and then walk away, or keep winning and playing until you get rid of all your money.