The Arcades:
With online game play nowadays, there's not that much reason anymore to go to the arcades. However, online gaming still can't compare to being in an actual place with lots of people who share the same hobby. For once, people are much more nicer face-to-face than they are online (and for some obvious reasons too
). And you normally kept in touch with the people who were there often one way or another.
CD Jewel Cases: OK, so there's things to like about these and things to hate. They tend to break rather easily. But they were more compact than the dvd-sized cases we get now and I was able to keep way more games in less space.
FPS's being one small part of the video game industry: I'm sorry, I like a good fps as much as any other person. My TF2 play times testify that. But back in the day there were some good fps's that you really liked and a bunch of adventure games, rpgs, action, puzzle, etc. etc. that had a good amount of good titles too. Now the fps's play a much larger role in video games, but the amount of games in the genre that stand out are about the same amount as back in the day when there weren't so many.
If you can think of any other thing that was done in the past but doesn't happen anymore and were good one way or another, feel free to add to the list.