Where does the guitar strap button go?

strap button

New acoustic guitars come with one strap button. You buy the other one (@ $5)  and attach it. This link shows 5 choices of places, and has tips on how to do it. Thank-you Dan Erlewine.
http://www.stewmac.com/How-To/Online_Resources/Hardware_Installation/Wheres_the_best_spot_for_your_strap_button.html