Imagine yourself out on a very hot and sunny day. You are exhausted, thirsty and sweating. You decide you need to drink cold water, need air conditioner, need to pee and even sit for a while to relax while using a WiFi to surf the internet. But you are out of cash.
There is a bank close to you. What do you do? I bet some banks might start watching out customers who are inside the banking hall not for any real transactions, but to use free facilities.