Are showers really more eco-friendly?

If there is something that I love is a good shower. I've always enjoyed that. I'm not a big fan of taking a bath -- you know the kind were you fill up the bathtub and you just soak for a while. It's nice to relax but I just prefer not to lay in water that is filthy with my own dirt, you know what I mean?

And I always thought that showers save water.

I don't own a bathtub. Actually for the last 6 years the only place where I've cleaned my self in a bathtub was in hotel rooms, and even there I always shower. And usually it takes me 7 to 10 min to shower.

Last week I've stayed in a hotel for 4 days -- No, I was not on holidays, I was working, a lot unfortunately. The hotel had a bathtub and one morning when I decided to shower I didn't noticed that the drain was closed -- you know, with the little black rubber cap -- and while I was showering the water started to accumulate. And I left it close, just to see just how much water I spend. I showered normally, like I do every day. And I was really surprised because when I was done, the bathtub was almost full. And I realized that I consume as much water in one shower as I would if I took a soak-in-bath. I was astonished, really!

I guess showering only saves water if you close the water while you scrub yourself, or wash your hair, but I never do that. At least in my home, the water takes a couple of minutes to heat up, and if I close the tap I have to wait a couple of minutes for the water to come out hot again -- which means more waste... 

I feel the need to be more environmentally concerned, I recycle, I don't have a car, I always use public transportation or walk. I try to buy things that are eco-friendly. But I guess there are just somethings I can't really avoid.