Why would a bitcoin sportsbook or casino site ban people from some countries? Would that not be against bitcoin's core peer to peer nature?
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One of the reasons that I can think of is the fact that Nitrogensports
offers P2P poker. Poker is a game that is obviously prone to various
forms of cheating (e.g. collusion between players, multi-accounting, bots
and other stuff). Certain countries provide basically no legit players, but
are a paradise for people involved in these different kinds of cheating.
Another reason is the abuse of Nitrogensports promotions. It is obviously
not in the interest of the operator when a single person takes part in the same
promotion multiple times and therefore they restrict players from countries, where
the loss due to promotion abuse is higher than the profit generated by legit players.