You are talking about credit, not money. Banks create actual state-backed money, which can be physically (or more likely electronically) paid to a third party after they've loaned it to you.

A better example would be if you were in the bar alone, and had no money, and instead just wrote an IOU on a bit of paper with your contact details. If we lived in a mythical 100% trustful utopia, then the barman would just accept this as money and so would anyone else in future who the barman needed to pay for anything. But we obviously don't live in such a society so unfortunately no, not anyone can just create money!