If I asked an exchange to list my 100% of supply to public..and 100% of the tokens
were bought already..who gets that money??
I don't understand your question. Mind explaining it in detail (and maybe in a slightly better english) ?
You don't ask an exchange to list your '100% of supply'.
You ask them to list your token. It will be then available for trading on this exchange.
People have to deposit tokens onto the exchange for others to be able to buy some.
And about what kind of money are you talking about? You have to pay the exchange to list your token.
So the exchanges gets money from you, in this case..