It sounds like you don't understand how banks operate. They only need to have reserves to back up customer deposits of a percentage, like 10% of total deposits,

It sounds like you don't understand how banks operate. They only need to have reserves to back up customer deposits of a percentage, like 10% of total deposits, which means they very much do loan your money to other people and invest it too. And your deposits are protected by the government in case the bank fails only up to a maximum per account, which can be $100k