Does anybody sew-in hidden inside pockets in their pants?

[@dam]

Hi everyone. On previous trips, I've used the Eagle Creek Hidden Pocket to hide my passport, money, and copies of important documents and numbers. However, the thing requires you wear a belt, and when you undo the belt, if you're not careful, the thing falls down your pants onto the floor. I was considering modifying all the pants I'll take traveling to have a hidden inside pocket sewn in, and then just keeping my stuff in a plastic bag that i'll throw into whatever I'm wearing that day. Has anybody done this?