Absence of accent marks

Today I saw MEDECINS SANS FRONTIERES (Doctors without borders) and below it its Czech version LÉKAŘI BEZ HRANIC both in block letters. What drew my attention is that the French decided to do away with their diacritics (médecins sans frontières) while the Czech flaunt theirs. Is that maybe because of that purported French rule that you shouldn't accent majuscules or is there a statement behind that?