If you do not watch terms and conditions you can even lose your money as the result. Especially if we are speaking about such things as online casinos. I do not play often it but I remember some awkward situations with betting services when I've decided to bet for some Dota pro squads. It was a bad experience as there are some services, I do not remember their name, that decided to take my money because I have not followed some of their terms. As a result, I've got my money but with big problems. I think such problems may occur with any services both for gambling and betting. So READ all terms and watch the South Park series about the terms and conditions you accept when buying something. It is really fun.
