Much more recently only (Wii/DS etc), and only for some EU countries. Australia in particular had a tiny little rating logo only until only a few years ago, and none before that. And they were even then removable stickers in most cases.
Eg Link to the Past
Castlevania IV - Konami games maintained the NES tradiation of silver boxes:
Later branching into other colours, but keeping the same template (it still keeps the same Konami text on the side
And I need not mention that PAL games rarely have worse actual art, and mostly have much nicer Japanese art. Good examples of vastly superior PAL covers are the Mega Man NES games, and most Final Fantasy games - PAL gets the beautiful simple Japanese logo covers, USA gets horrific kids movie posters.
And there's this:
Also only some territories. Australia was unaffected.