Growing up, I wasted water every night without fail! But I cut back after my parents moved to the Philippines about 20 years ago, and I visited them. When you have to heat up water on the stove to take a hot "shower," your relationship with water changes forever.
When I've been in the First World for too long though, I get complacent about conserving water. Since we were just there though, I'm much better about turning the water off when I'm brushing my teeth. Water conservation is definitely a value that I want the kids to pick up on!
Do you turn the water on and let it run while you're brushing your teeth?