Totally. "Science" requires precision because science in many ways is the mechanism by which we learn truths with greater and greater precision. That doesn't mean though that science naturally abhors imprecise "for-scale" measurements though- they just reserve them for illustration and avoid using them for the actual science. (e.g., http://imgur.com/gallery/ESp2j - marianas trench scale)

Yep can understand that. Its important to visualise values and comparing to reference points is fine.

This comes to mind for unit conversions: http://www.weirdconverter.com

That was an Imgur meme first. One of the original Imgur memes at that.