Here you go again, you 'mericans, with your screening procedures.
Just kidding. Each to his own. No surgeon in Sweden would dream of performing a colonscopy on a perfectly well person with no symptoms pointing to bowel desease or malignancy.
As far as I know, there are no scientific evidence on a population basis suggesting there is anything to gain with such routines.
For any individual, the case is of course different.
Disclaimer: Excuse my bad spelling, the Spell Check refuses to work!