Note that the ban was for sales to minors (under the age of 18) not to all citizens. It also disallowed advertisement, of course, so probably there was a notice

Note that the ban was for sales to minors (under the age of 18) not to all citizens. It also disallowed advertisement, of course, so probably there was a noticeable impact on sales. It probably didn't stop teenagers from getting the game anyhow as piracy was rampant those days and being "on the index" made it extra attractive to many. The situation has improved a lot these days after an amendment in 2003. There is an industry board (USK) giving age recommendations (0+, 6+, 12+, 16+, 18+) and if a game has been rated 18+, shops will not sell it to minors. Importantly, if a game has been rated by this board, it can no longer be put onto the index maintained by that Federal Review Board for Media Harmful to Minors. So the far-reaching restrictions against advertisement no longer apply.