There is a time and a place for cropping but, as much as possible, I prefer to shoot for the end result and compose my shot as I want to see it in print. Anyone can crop a photo to eliminate surrounding distractions or bring their main subject closer. I’m not saying that I never do that; I just try to avoid it.
Relying on this technique can make you lazier and allow you to go nuts shooting hundreds of shots because you know you can crop them to something pleasing later. However, stop and think about that statement for a minute. You can crop them later. Hmmm… How much time is that going to take? Also, when you crop too much, you will limit how large you can print a quality photo from it.
Here are some examples of photos as composed in-camera…
And these required some cropping…
Sheila Karner Photography 
I absolutely agree – composing in-camera to what you want always beats cropping stuff out. Unless of course you want a square shot but don’t have a medium format camera… but that’s a different story of sorts.
I haven’t done square yet, but I do plan on adding some to a wall or two in my home sometime soon!