All of the requirements of providing identifying information are done for the mutual protection of the players and operators. The use of legal names, addresses, and other vital statistics such as your social security number are to ensure that any activity on an account is being carried out by the actual player, and not a scammer that obtained only part of your information. In some cases, banking transactions may even require scans or pictures of physical documents to ensure that money is being transferred to or from the real you. While these examples are inconvenient and annoying in the moment, the added protection afforded by this level of caution is more than worth it in the end.