Do some people fill their flasks with other drinks?

You can fill it with water but outside of that, you'll want to stick with liquor. The metal of the flask and other liquids don't work well together.

I worked as a door to door salesman a few years back and filled one with water throughout the day.

I've always wanted a flask to fill it with liquor and take it everywhere.

It doesnt matter u could fill that biitch up with anything u want u could fill it up with ur own pee it dont matter what other people do just do what u want to

I'm sure some teens will do it to give the illusion that they're drinking to look cool.